httpd/server/vhost.c

	vhost.c revision b88f887ed5554d9050d97f9a56a89ae62bdbd906
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/* ====================================================================
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * The Apache Software License, Version 1.1
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * Copyright (c) 2000 The Apache Software Foundation.  All rights
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * reserved.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * Redistribution and use in source and binary forms, with or without
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * modification, are permitted provided that the following conditions
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * are met:
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * 1. Redistributions of source code must retain the above copyright
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *    notice, this list of conditions and the following disclaimer.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * 2. Redistributions in binary form must reproduce the above copyright
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *    notice, this list of conditions and the following disclaimer in
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *    the documentation and/or other materials provided with the
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *    distribution.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * 3. The end-user documentation included with the redistribution,
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *    if any, must include the following acknowledgment:
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *       "This product includes software developed by the
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *        Apache Software Foundation (http://www.apache.org/)."
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *    Alternately, this acknowledgment may appear in the software itself,
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *    if and wherever such third-party acknowledgments normally appear.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * 4. The names "Apache" and "Apache Software Foundation" must
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *    not be used to endorse or promote products derived from this
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose *    software without prior written permission. For written
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose *    permission, please contact apache@apache.org.
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose *
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * 5. Products derived from this software may not be called "Apache",
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose *    nor may "Apache" appear in their name, without prior written
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose *    permission of the Apache Software Foundation.
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose *
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * SUCH DAMAGE.
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * ====================================================================
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose *
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * This software consists of voluntary contributions made by many
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * individuals on behalf of the Apache Software Foundation.  For more
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * information on the Apache Software Foundation, please see
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * <http://www.apache.org/>.
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose *
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * Portions of this software are based upon public domain software
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * originally written at the National Center for Supercomputing Applications,
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * University of Illinois, Urbana-Champaign.
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose */
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose/*
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * http_vhost.c: functions pertaining to virtual host addresses
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose *  (configuration and run-time)
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose */
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#define CORE_PRIVATE
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include "ap_config.h"
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include "httpd.h"
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include "http_config.h"
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include "http_log.h"
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include "http_vhost.h"
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include "http_protocol.h"
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include "http_core.h"
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include "apr_strings.h"
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#ifdef HAVE_ARPA_INET_H
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include <arpa/inet.h>
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#endif
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#ifdef HAVE_NETINET_IN_H
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include <netinet/in.h>
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#endif
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#ifdef HAVE_SYS_SOCKET_H
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include <sys/socket.h>
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#endif
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#ifdef HAVE_NETDB_H
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#include <netdb.h>
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#endif
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose#ifdef HAVE_STRINGS_H
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose#include <strings.h>
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose#endif
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/*
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * After all the definitions there's an explanation of how it's all put
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * together.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose/* meta-list of name-vhosts.  Each server_rec can be in possibly multiple
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * lists of name-vhosts.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bosetypedef struct name_chain name_chain;
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bosestruct name_chain {
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    name_chain *next;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    server_addr_rec *sar;   /* the record causing it to be in
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose                 * this chain (needed for port comparisons) */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    server_rec *server;     /* the server to use on a match */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose};
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/* meta-list of ip addresses.  Each server_rec can be in possibly multiple
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * hash chains since it can have multiple ips.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bosetypedef struct ipaddr_chain ipaddr_chain;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bosestruct ipaddr_chain {
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    ipaddr_chain *next;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    server_addr_rec *sar;   /* the record causing it to be in
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose                 * this chain (need for both ip addr and port
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose                 * comparisons) */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    server_rec *server;     /* the server to use if this matches */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    name_chain *names;      /* if non-NULL then a list of name-vhosts
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose                     * sharing this address */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose};
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/* This defines the size of the hash apr_table_t used for hashing ip addresses
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * of virtual hosts.  It must be a power of two.
5dcf3ffa3aa228701a79556dc0b889dba0aac535Sumit Bose */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose#ifndef IPHASH_TABLE_SIZE
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose#define IPHASH_TABLE_SIZE 256
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose#endif
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/* A (n) bucket hash table, each entry has a pointer to a server rec and
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * a pointer to the other entries in that bucket.  Each individual address,
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * even for virtualhosts with multiple addresses, has an entry in this hash
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * table.  There are extra buckets for _default_, and name-vhost entries.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * Note that after config time this is constant, so it is thread-safe.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bosestatic ipaddr_chain *iphash_table[IPHASH_TABLE_SIZE];
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/* dump out statistics about the hash function */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/* #define IPHASH_STATISTICS */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/* list of the _default_ servers */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bosestatic ipaddr_chain *default_list;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/* list of the NameVirtualHost addresses */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bosestatic server_addr_rec *name_vhost_list;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bosestatic server_addr_rec **name_vhost_list_tail;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/*
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * How it's used:
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * The ip address determines which chain in iphash_table is interesting, then
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * a comparison is done down that chain to find the first ipaddr_chain whose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * sar matches the address:port pair.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * If that ipaddr_chain has names == NULL then you're done, it's an ip-vhost.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * Otherwise it's a name-vhost list, and the default is the server in the
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * ipaddr_chain record.  We tuck away the ipaddr_chain record in the
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * conn_rec field vhost_lookup_data.  Later on after the headers we get a
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * second chance, and we use the name_chain to figure out what name-vhost
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * matches the headers.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * If there was no ip address match in the iphash_table then do a lookup
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * in the default_list.
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose *
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * How it's put together ... well you should be able to figure that out
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * from how it's used.  Or something like that.
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose */
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose/* called at the beginning of the config */
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bosevoid ap_init_vhost_config(apr_pool_t *p)
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose{
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    memset(iphash_table, 0, sizeof(iphash_table));
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    default_list = NULL;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    name_vhost_list = NULL;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    name_vhost_list_tail = &name_vhost_list;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose}
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose/*
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * Parses a host of the form <address>[:port]
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose * paddr is used to create a list in the order of input
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * **paddr is the ->next pointer of the last entry (or s->addrs)
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * *paddr is the variable used to keep track of **paddr between calls
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose * port is the default port to assume
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose */
a0ab15ceb80290db80c2052520830a95390de385Sumit Bosestatic const char *get_addresses(apr_pool_t *p, const char *w_,
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose                 server_addr_rec ***paddr, unsigned port)
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose{
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    struct hostent *hep;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    unsigned long my_addr;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    server_addr_rec *sar;
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    char *t;
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    int i, is_an_ip_addr;
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    char *w;
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    if (*w_ == 0)
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    return NULL;
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    w=apr_pstrdup(p, w_);
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    t = strchr(w, ':');
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    if (t) {
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    if (strcmp(t + 1, "*") == 0) {
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose        port = 0;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    }
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    else if ((i = atoi(t + 1))) {
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose        port = i;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    }
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    else {
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose        return ":port must be numeric";
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    }
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    *t = 0;
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    }
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    is_an_ip_addr = 0;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    if (strcmp(w, "*") == 0) {
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    my_addr = htonl(INADDR_ANY);
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    is_an_ip_addr = 1;
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    }
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    else if (strcasecmp(w, "_default_") == 0
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose         || strcmp(w, "255.255.255.255") == 0) {
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    my_addr = DEFAULT_VHOST_ADDR;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    is_an_ip_addr = 1;
576ad637181b80d39a4e136c9afbf34c57f76156Sumit Bose    }
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    else if ((my_addr = apr_inet_addr(w)) != INADDR_NONE) {
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    is_an_ip_addr = 1;
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    }
a0ab15ceb80290db80c2052520830a95390de385Sumit Bose    if (is_an_ip_addr) {
    sar = apr_pcalloc(p, sizeof(server_addr_rec));
    **paddr = sar;
    *paddr = &sar->next;
    sar->host_addr.s_addr = my_addr;
    sar->host_port = port;
    sar->virthost = apr_pstrdup(p, w);
    return NULL;
    }

    hep = gethostbyname(w);

    if ((!hep) || (hep->h_addrtype != AF_INET || !hep->h_addr_list[0])) {
    ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, NULL,
        "Cannot resolve host name %s --- ignoring!", w);
    return NULL;
    }

    for (i = 0; hep->h_addr_list[i]; ++i) {
    sar = apr_pcalloc(p, sizeof(server_addr_rec));
    **paddr = sar;
    *paddr = &sar->next;
    sar->host_addr = *(struct in_addr *) hep->h_addr_list[i];
    sar->host_port = port;
    sar->virthost = apr_pstrdup(p, w);
    }

    return NULL;
}


/* parse the <VirtualHost> addresses */
const char *ap_parse_vhost_addrs(apr_pool_t *p, const char *hostname, server_rec *s)
{
    server_addr_rec **addrs;
    const char *err;

    /* start the list of addreses */
    addrs = &s->addrs;
    while (hostname[0]) {
    err = get_addresses(p, ap_getword_conf(p, &hostname), &addrs, s->port);
    if (err) {
        *addrs = NULL;
        return err;
    }
    }
    /* terminate the list */
    *addrs = NULL;
    if (s->addrs) {
    if (s->addrs->host_port) {
        /* override the default port which is inherited from main_server */
        s->port = s->addrs->host_port;
    }
    }
    return NULL;
}


const char *ap_set_name_virtual_host (cmd_parms *cmd, void *dummy,
                      const char *arg)
{
    /* use whatever port the main server has at this point */
    return get_addresses(cmd->pool, arg, &name_vhost_list_tail,
                cmd->server->port);
}


/* hash apr_table_t statistics, keep this in here for the beta period so
 * we can find out if the hash function is ok
 */
#ifdef IPHASH_STATISTICS
static int iphash_compare(const void *a, const void *b)
{
    return (*(const int *) b - *(const int *) a);
}


static void dump_iphash_statistics(server_rec *main_s)
{
    unsigned count[IPHASH_TABLE_SIZE];
    int i;
    ipaddr_chain *src;
    unsigned total;
    char buf[HUGE_STRING_LEN];
    char *p;

    total = 0;
    for (i = 0; i < IPHASH_TABLE_SIZE; ++i) {
    count[i] = 0;
    for (src = iphash_table[i]; src; src = src->next) {
        ++count[i];
        if (i < IPHASH_TABLE_SIZE) {
        /* don't count the slop buckets in the total */
        ++total;
        }
    }
    }
    qsort(count, IPHASH_TABLE_SIZE, sizeof(count[0]), iphash_compare);
    p = buf + apr_snprintf(buf, sizeof(buf),
            "iphash: total hashed = %u, avg chain = %u, "
            "chain lengths (count x len):",
            total, total / IPHASH_TABLE_SIZE);
    total = 1;
    for (i = 1; i < IPHASH_TABLE_SIZE; ++i) {
    if (count[i - 1] != count[i]) {
        p += apr_snprintf(p, sizeof(buf) - (p - buf), " %ux%u",
                 total, count[i - 1]);
        total = 1;
    }
    else {
        ++total;
    }
    }
    p += apr_snprintf(p, sizeof(buf) - (p - buf), " %ux%u",
             total, count[IPHASH_TABLE_SIZE - 1]);
    ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_DEBUG, main_s, buf);
}
#endif


/* This hashing function is designed to get good distribution in the cases
 * where the server is handling entire "networks" of servers.  i.e. a
 * whack of /24s.  This is probably the most common configuration for
 * ISPs with large virtual servers.
 *
 * NOTE: This function is symmetric (i.e. collapses all 4 octets
 * into one), so machine byte order (big/little endianness) does not matter.
 *
 * Hash function provided by David Hankins.
 */
static apr_inline unsigned hash_inaddr(unsigned key)
{
    key ^= (key >> 16);
    return ((key >> 8) ^ key) % IPHASH_TABLE_SIZE;
}


static ipaddr_chain *new_ipaddr_chain(apr_pool_t *p,
                    server_rec *s, server_addr_rec *sar)
{
    ipaddr_chain *new;

    new = apr_palloc(p, sizeof(*new));
    new->names = NULL;
    new->server = s;
    new->sar = sar;
    new->next = NULL;
    return new;
}


static name_chain *new_name_chain(apr_pool_t *p, server_rec *s, server_addr_rec *sar)
{
    name_chain *new;

    new = apr_palloc(p, sizeof(*new));
    new->server = s;
    new->sar = sar;
    new->next = NULL;
    return new;
}


static apr_inline ipaddr_chain *find_ipaddr(struct in_addr *server_ip,
    unsigned port)
{
    unsigned bucket;
    ipaddr_chain *trav;
    unsigned addr;

    /* scan the hash apr_table_t for an exact match first */
    addr = server_ip->s_addr;
    bucket = hash_inaddr(addr);
    for (trav = iphash_table[bucket]; trav; trav = trav->next) {
    server_addr_rec *sar = trav->sar;
    if ((sar->host_addr.s_addr == addr)
        && (sar->host_port == 0 || sar->host_port == port
        || port == 0)) {
        return trav;
    }
    }
    return NULL;
}


static ipaddr_chain *find_default_server(unsigned port)
{
    server_addr_rec *sar;
    ipaddr_chain *trav;

    for (trav = default_list; trav; trav = trav->next) {
        sar = trav->sar;
        if (sar->host_port == 0 || sar->host_port == port) {
            /* match! */
        return trav;
        }
    }
    return NULL;
}

static void dump_a_vhost(apr_file_t *f, ipaddr_chain *ic)
{
    name_chain *nc;
    int len;
    char buf[MAX_STRING_LEN];

    if (ic->sar->host_addr.s_addr == DEFAULT_VHOST_ADDR) {
    len = apr_snprintf(buf, sizeof(buf), "_default_:%u",
        ic->sar->host_port);
    }
    else if (ic->sar->host_addr.s_addr == INADDR_ANY) {
    len = apr_snprintf(buf, sizeof(buf), "*:%u",
        ic->sar->host_port);
    }
    else {
    len = apr_snprintf(buf, sizeof(buf), "%pA:%u",
        &ic->sar->host_addr, ic->sar->host_port);
    }
    if (ic->sar->host_port == 0) {
    buf[len-1] = '*';
    }
    if (ic->names == NULL) {
    apr_fprintf(f, "%-22s %s (%s:%u)\n", buf, ic->server->server_hostname,
        ic->server->defn_name, ic->server->defn_line_number);
    return;
    }
    apr_fprintf(f, "%-22s is a NameVirtualHost\n"
        "%22s default server %s (%s:%u)\n",
        buf, "", ic->server->server_hostname,
        ic->server->defn_name, ic->server->defn_line_number);
    for (nc = ic->names; nc; nc = nc->next) {
    if (nc->sar->host_port) {
        apr_fprintf(f, "%22s port %u ", "", nc->sar->host_port);
    }
    else {
        apr_fprintf(f, "%22s port * ", "");
    }
    apr_fprintf(f, "namevhost %s (%s:%u)\n", nc->server->server_hostname,
        nc->server->defn_name, nc->server->defn_line_number);
    }
}

static void dump_vhost_config(apr_file_t *f)
{
    ipaddr_chain *ic;
    int i;

    apr_fprintf(f, "VirtualHost configuration:\n");
    for (i = 0; i < IPHASH_TABLE_SIZE; ++i) {
    for (ic = iphash_table[i]; ic; ic = ic->next) {
        dump_a_vhost(f, ic);
    }
    }
    if (default_list) {
    apr_fprintf(f, "wildcard NameVirtualHosts and _default_ servers:\n");
    for (ic = default_list; ic; ic = ic->next) {
        dump_a_vhost(f, ic);
    }
    }
}

/*
 * Two helper functions for ap_fini_vhost_config()
 */
static int add_name_vhost_config(apr_pool_t *p, server_rec *main_s, server_rec *s,
                 server_addr_rec *sar, ipaddr_chain *ic)
{
    /* the first time we encounter a NameVirtualHost address
     * ic->server will be NULL, on subsequent encounters
     * ic->names will be non-NULL.
     */
    if (ic->names || ic->server == NULL) {
    name_chain *nc = new_name_chain(p, s, sar);
    nc->next = ic->names;
    ic->names = nc;
    ic->server = s;
    if (sar->host_port != ic->sar->host_port) {
        /* one of the two is a * port, the other isn't */
        ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, main_s,
            "VirtualHost %s:%u -- mixing * "
            "ports and non-* ports with "
            "a NameVirtualHost address is not supported,"
            " proceeding with undefined results",
            sar->virthost, sar->host_port);
    }
    return 1;
    }
    else {
    /* IP-based vhosts are handled by the caller */
    return 0;
    }
}

static void remove_unused_name_vhosts(server_rec *main_s, ipaddr_chain **pic)
{
    while (*pic) {
    ipaddr_chain *ic = *pic;

    if (ic->server == NULL) {
        ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, main_s,
             "NameVirtualHost %s:%u has no VirtualHosts",
             ic->sar->virthost, ic->sar->host_port);
        *pic = ic->next;
    }
    else if (ic->names == NULL) {
        /* if server != NULL and names == NULL then we're done
         * looking at NameVirtualHosts
         */
        break;
    }
    else {
        pic = &ic->next;
    }
    }
}

/* compile the tables and such we need to do the run-time vhost lookups */
void ap_fini_vhost_config(apr_pool_t *p, server_rec *main_s)
{
    server_addr_rec *sar;
    int has_default_vhost_addr;
    server_rec *s;
    int i;
    ipaddr_chain **iphash_table_tail[IPHASH_TABLE_SIZE];

    /* terminate the name_vhost list */
    *name_vhost_list_tail = NULL;

    /* Main host first */
    s = main_s;

    if (!s->server_hostname) {
    s->server_hostname = ap_get_local_host(p);
    }

    /* initialize the tails */
    for (i = 0; i < IPHASH_TABLE_SIZE; ++i) {
    iphash_table_tail[i] = &iphash_table[i];
    }

    /* The first things to go into the hash apr_table_t are the NameVirtualHosts
     * Since name_vhost_list is in the same order that the directives
     * occured in the config file, we'll copy it in that order.
     */
    for (sar = name_vhost_list; sar; sar = sar->next) {
    unsigned bucket = hash_inaddr(sar->host_addr.s_addr);
    ipaddr_chain *ic = new_ipaddr_chain(p, NULL, sar);

    if (sar->host_addr.s_addr != INADDR_ANY) {
        *iphash_table_tail[bucket] = ic;
        iphash_table_tail[bucket] = &ic->next;
    }
    else {
        /* A wildcard NameVirtualHost goes on the default_list so
         * that it can catch incoming requests on any address.
         */
        ic->next = default_list;
        default_list = ic;
    }
    /* Notice that what we've done is insert an ipaddr_chain with
     * both server and names NULL. This fact is used to spot name-
     * based vhosts in add_name_vhost_config().
     */
    }

    /* The next things to go into the hash apr_table_t are the virtual hosts
     * themselves.  They're listed off of main_s->next in the reverse
     * order they occured in the config file, so we insert them at
     * the iphash_table_tail but don't advance the tail.
     */

    for (s = main_s->next; s; s = s->next) {
    has_default_vhost_addr = 0;
    for (sar = s->addrs; sar; sar = sar->next) {
        ipaddr_chain *ic;

        if (sar->host_addr.s_addr == DEFAULT_VHOST_ADDR
        || sar->host_addr.s_addr == INADDR_ANY) {
        ic = find_default_server(sar->host_port);
        if (!ic || !add_name_vhost_config(p, main_s, s, sar, ic)) {
            if (ic && ic->sar->host_port != 0) {
            ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING,
                0, main_s, "_default_ VirtualHost overlap on port %u,"
                " the first has precedence", sar->host_port);
            }
            ic = new_ipaddr_chain(p, s, sar);
            ic->next = default_list;
            default_list = ic;
        }
        has_default_vhost_addr = 1;
        }
        else {
        /* see if it matches something we've already got */
        ic = find_ipaddr(&sar->host_addr, sar->host_port);

        if (!ic) {
            unsigned bucket = hash_inaddr(sar->host_addr.s_addr);

            ic = new_ipaddr_chain(p, s, sar);
            ic->next = *iphash_table_tail[bucket];
            *iphash_table_tail[bucket] = ic;
        }
        else if (!add_name_vhost_config(p, main_s, s, sar, ic)) {
            ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_WARNING, 0, main_s,
                "VirtualHost %s:%u overlaps with "
                "VirtualHost %s:%u, the first has precedence, "
                "perhaps you need a NameVirtualHost directive",
                sar->virthost, sar->host_port,
                ic->sar->virthost, ic->sar->host_port);
            ic->sar = sar;
            ic->server = s;
        }
        }
    }

    /* Ok now we want to set up a server_hostname if the user was
     * silly enough to forget one.
     * XXX: This is silly we should just crash and burn.
     */
    if (!s->server_hostname) {
        if (has_default_vhost_addr) {
        s->server_hostname = main_s->server_hostname;
        }
        else if (!s->addrs) {
        /* what else can we do?  at this point this vhost has
            no configured name, probably because they used
            DNS in the VirtualHost statement.  It's disabled
            anyhow by the host matching code.  -djg */
        s->server_hostname =
            apr_pstrdup(p, "bogus_host_without_forward_dns");
        }
        else {
        struct hostent *h;

        if ((h = gethostbyaddr((char *) &(s->addrs->host_addr),
                    sizeof(struct in_addr), AF_INET))) {
            s->server_hostname = apr_pstrdup(p, (char *) h->h_name);
        }
        else {
            /* again, what can we do?  They didn't specify a
               ServerName, and their DNS isn't working. -djg */
            ap_log_error(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, main_s,
                "Failed to resolve server name "
                "for %s (check DNS) -- or specify an explicit "
                "ServerName",
                inet_ntoa(s->addrs->host_addr));
            s->server_hostname =
            apr_pstrdup(p, "bogus_host_without_reverse_dns");
        }
        }
    }
    }

    /* now go through and delete any NameVirtualHosts that didn't have any
     * hosts associated with them.  Lamers.
     */
    for (i = 0; i < IPHASH_TABLE_SIZE; ++i) {
    remove_unused_name_vhosts(main_s, &iphash_table[i]);
    }
    remove_unused_name_vhosts(main_s, &default_list);

#ifdef IPHASH_STATISTICS
    dump_iphash_statistics(main_s);
#endif
    if (getenv("DUMP_VHOSTS")) {
        apr_file_t *thefile = NULL;
        apr_open_stderr(&thefile, p);
    dump_vhost_config(thefile);
    }
}


/*****************************************************************************
 * run-time vhost matching functions
 */

/* Lowercase and remove any trailing dot and/or :port from the hostname,
 * and check that it is sane.
 */
static void fix_hostname(request_rec *r)
{
    char *host = apr_palloc(r->pool, strlen(r->hostname) + 1);
    const char *src;
    char *dst;

    /* check and copy the host part */
    src = r->hostname;
    dst = host;
    while (*src) {
    if (!apr_isalnum(*src) && *src != '.' && *src != '-') {
        if (*src == ':')
        break;
        else
        goto bad;
    } else {
        *dst++ = *src++;
    }
    }
    /* check the port part */
    if (*src++ == ':') {
    while (*src) {
        if (!apr_isdigit(*src++)) {
        goto bad;
        }
    }
    }
    /* strip trailing gubbins */
    if (dst > host && dst[-1] == '.') {
    dst[-1] = '\0';
    } else {
    dst[0] = '\0';
    }

    r->hostname = host;
    return;

bad:
    r->status = HTTP_BAD_REQUEST;
    ap_log_rerror(APLOG_MARK, APLOG_NOERRNO|APLOG_ERR, 0, r,
          "Client sent malformed Host header");
    return;
}


/* return 1 if host matches ServerName or ServerAliases */
static int matches_aliases(server_rec *s, const char *host)
{
    int i;
    apr_array_header_t *names;

    /* match ServerName */
    if (!strcasecmp(host, s->server_hostname)) {
    return 1;
    }

    /* search all the aliases from ServerAlias directive */
    names = s->names;
    if (names) {
    char **name = (char **) names->elts;
    for (i = 0; i < names->nelts; ++i) {
        if(!name[i]) continue;
        if (!strcasecmp(host, name[i]))
        return 1;
    }
    }
    names = s->wild_names;
    if (names) {
    char **name = (char **) names->elts;
    for (i = 0; i < names->nelts; ++i) {
        if(!name[i]) continue;
        if (!ap_strcasecmp_match(host, name[i]))
        return 1;
    }
    }
    return 0;
}


/* Suppose a request came in on the same socket as this r, and included
 * a header "Host: host:port", would it map to r->server?  It's more
 * than just that though.  When we do the normal matches for each request
 * we don't even bother considering Host: etc on non-namevirtualhosts,
 * we just call it a match.  But here we require the host:port to match
 * the ServerName and/or ServerAliases.
 */
API_EXPORT(int) ap_matches_request_vhost(request_rec *r, const char *host,
    unsigned port)
{
    server_rec *s;
    server_addr_rec *sar;

    s = r->server;

    /* search all the <VirtualHost> values */
    /* XXX: If this is a NameVirtualHost then we may not be doing the Right Thing
     * consider:
     *
     *     NameVirtualHost 10.1.1.1
     *     <VirtualHost 10.1.1.1>
     *     ServerName v1
     *     </VirtualHost>
     *     <VirtualHost 10.1.1.1>
     *     ServerName v2
     *     </VirtualHost>
     *
     * Suppose r->server is v2, and we're asked to match "10.1.1.1".  We'll say
     * "yup it's v2", when really it isn't... if a request came in for 10.1.1.1
     * it would really go to v1.
     */
    for (sar = s->addrs; sar; sar = sar->next) {
    if ((sar->host_port == 0 || port == sar->host_port)
        && !strcasecmp(host, sar->virthost)) {
        return 1;
    }
    }

    /* the Port has to match now, because the rest don't have ports associated
     * with them. */
    if (port != s->port) {
    return 0;
    }

    return matches_aliases(s, host);
}


static void check_hostalias(request_rec *r)
{
    /*
     * Even if the request has a Host: header containing a port we ignore
     * that port.  We always use the physical port of the socket.  There
     * are a few reasons for this:
     *
     * - the default of 80 or 443 for SSL is easier to handle this way
     * - there is less of a possibility of a security problem
     * - it simplifies the data structure
     * - the client may have no idea that a proxy somewhere along the way
     *   translated the request to another ip:port
     * - except for the addresses from the VirtualHost line, none of the other
     *   names we'll match have ports associated with them
     */
    const char *host = r->hostname;
    unsigned port = ntohs(r->connection->local_addr.sin_port);
    server_rec *s;
    server_rec *last_s;
    name_chain *src;

    last_s = NULL;

    /* Recall that the name_chain is a list of server_addr_recs, some of
     * whose ports may not match.  Also each server may appear more than
     * once in the chain -- specifically, it will appear once for each
     * address from its VirtualHost line which matched.  We only want to
     * do the full ServerName/ServerAlias comparisons once for each
     * server, fortunately we know that all the VirtualHost addresses for
     * a single server are adjacent to each other.
     */

    for (src = r->connection->vhost_lookup_data; src; src = src->next) {
        server_addr_rec *sar;

    /* We only consider addresses on the name_chain which have a matching
     * port
     */
    sar = src->sar;
    if (sar->host_port != 0 && port != sar->host_port) {
        continue;
    }

        s = src->server;

    /* does it match the virthost from the sar? */
    if (!strcasecmp(host, sar->virthost)) {
        goto found;
    }

    if (s == last_s) {
        /* we've already done ServerName and ServerAlias checks for this
         * vhost
         */
        continue;
    }
    last_s = s;

    if (matches_aliases(s, host)) {
        goto found;
    }
    }
    return;

found:
    /* s is the first matching server, we're done */
    r->server = s;
}


static void check_serverpath(request_rec *r)
{
    server_rec *s;
    server_rec *last_s;
    name_chain *src;
    /* use AP func here. */
    unsigned port = ntohs(r->connection->local_addr.sin_port);

    /*
     * This is in conjunction with the ServerPath code in http_core, so we
     * get the right host attached to a non- Host-sending request.
     *
     * See the comment in check_hostalias about how each vhost can be
     * listed multiple times.
     */

    last_s = NULL;
    for (src = r->connection->vhost_lookup_data; src; src = src->next) {
    /* We only consider addresses on the name_chain which have a matching
     * port
     */
    if (src->sar->host_port != 0 && port != src->sar->host_port) {
        continue;
    }

        s = src->server;
    if (s == last_s) {
        continue;
    }
    last_s = s;

        if (s->path && !strncmp(r->uri, s->path, s->pathlen) &&
            (s->path[s->pathlen - 1] == '/' ||
             r->uri[s->pathlen] == '/' ||
             r->uri[s->pathlen] == '\0')) {
            r->server = s;
        return;
    }
    }
}


void ap_update_vhost_from_headers(request_rec *r)
{
    /* must set this for HTTP/1.1 support */
    if (r->hostname || (r->hostname = apr_table_get(r->headers_in, "Host"))) {
    fix_hostname(r);
    if (r->status != HTTP_OK)
        return;
    }
    /* check if we tucked away a name_chain */
    if (r->connection->vhost_lookup_data) {
        if (r->hostname)
            check_hostalias(r);
        else
            check_serverpath(r);
    }
}


/* Called for a new connection which has a known local_addr.  Note that the
 * new connection is assumed to have conn->server == main server.
 */
void ap_update_vhost_given_ip(conn_rec *conn)
{
    ipaddr_chain *trav;
    unsigned port = ntohs(conn->local_addr.sin_port);

    /* scan the hash apr_table_t for an exact match first */
    trav = find_ipaddr(&conn->local_addr.sin_addr, port);
    if (trav) {
    /* save the name_chain for later in case this is a name-vhost */
    conn->vhost_lookup_data = trav->names;
    conn->base_server = trav->server;
    return;
    }

    /* maybe there's a default server or wildcard name-based vhost
     * matching this port
     */
    trav = find_default_server(port);
    if (trav) {
    conn->vhost_lookup_data = trav->names;
    conn->base_server = trav->server;
    return;
    }

    /* otherwise we're stuck with just the main server
     * and no name-based vhosts
     */
    conn->vhost_lookup_data = NULL;
}