/* Copyright 1999-2004 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "mod_proxy.h"

#define CORE_PRIVATE

#include "http_log.h"
#include "http_vhost.h"
#include "http_request.h"

/* Some WWW schemes and their default ports; this is basically /etc/services */
/* This will become global when the protocol abstraction comes */
static struct proxy_services defports[] =
{
    {"http", DEFAULT_HTTP_PORT},
    {"ftp", DEFAULT_FTP_PORT},
    {"https", DEFAULT_HTTPS_PORT},
    {"gopher", DEFAULT_GOPHER_PORT},
    {"nntp", DEFAULT_NNTP_PORT},
    {"wais", DEFAULT_WAIS_PORT},
    {"snews", DEFAULT_SNEWS_PORT},
    {"prospero", DEFAULT_PROSPERO_PORT},
    {NULL, -1}                  /* unknown port */
};

/*
 * A Web proxy module. Stages:
 *
 *  translate_name: set filename to proxy:<URL>
 *  type_checker:   set type to PROXY_MAGIC_TYPE if filename begins proxy:
 *  fix_ups:        convert the URL stored in the filename to the
 *                  canonical form.
 *  handler:        handle proxy requests
 */

/* -------------------------------------------------------------- */
/* Translate the URL into a 'filename' */

static int alias_match(const char *uri, const char *alias_fakename)
{
    const char *end_fakename = alias_fakename + strlen(alias_fakename);
    const char *aliasp = alias_fakename, *urip = uri;

    while (aliasp < end_fakename) {
        if (*aliasp == '/') {
            /*
             * any number of '/' in the alias matches any number in the
             * supplied URI, but there must be at least one...
             */
            if (*urip != '/')
                return 0;

            while (*aliasp == '/')
                ++aliasp;
            while (*urip == '/')
                ++urip;
        }
        else {
            /* Other characters are compared literally */
            if (*urip++ != *aliasp++)
                return 0;
        }
    }

    /* Check last alias path component matched all the way */

    if (aliasp[-1] != '/' && *urip != '\0' && *urip != '/')
        return 0;

    /*
     * Return number of characters from URI which matched (may be greater
     * than length of alias, since we may have matched doubled slashes)
     */

    return urip - uri;
}

/* Detect if an absoluteURI should be proxied or not.  Note that we
 * have to do this during this phase because later phases are
 * "short-circuiting"... i.e. translate_names will end when the first
 * module returns OK.  So for example, if the request is something like:
 *
 * GET http://othervhost/cgi-bin/printenv HTTP/1.0
 *
 * mod_alias will notice the /cgi-bin part and ScriptAlias it and
 * short-circuit the proxy... just because of the ordering in the
 * configuration file.
 */
static int proxy_detect(request_rec *r)
{
    void *sconf = r->server->module_config;
    proxy_server_conf *conf;

    conf = (proxy_server_conf *)ap_get_module_config(sconf, &proxy_module);

    if (conf->req && r->parsed_uri.scheme) {
        /* but it might be something vhosted */
        if (!(r->parsed_uri.hostname
              && !strcasecmp(r->parsed_uri.scheme, ap_http_method(r))
              && ap_matches_request_vhost(r, r->parsed_uri.hostname,
        r->parsed_uri.port_str ? r->parsed_uri.port : ap_default_port(r)))) {
            r->proxyreq = STD_PROXY;
            r->uri = r->unparsed_uri;
            r->filename = ap_pstrcat(r->pool, "proxy:", r->uri, NULL);
            r->handler = "proxy-server";
        }
    }
    /* We need special treatment for CONNECT proxying: it has no scheme part */
    else if (conf->req && r->method_number == M_CONNECT
             && r->parsed_uri.hostname
             && r->parsed_uri.port_str) {
        r->proxyreq = STD_PROXY;
        r->uri = r->unparsed_uri;
        r->filename = ap_pstrcat(r->pool, "proxy:", r->uri, NULL);
        r->handler = "proxy-server";
    }
    return DECLINED;
}

static int proxy_trans(request_rec *r)
{
    void *sconf = r->server->module_config;
    proxy_server_conf *conf =
    (proxy_server_conf *)ap_get_module_config(sconf, &proxy_module);
    int i, len;
    struct proxy_alias *ent = (struct proxy_alias *)conf->aliases->elts;

    if (r->proxyreq != NOT_PROXY) {
        /*
         * someone has already set up the proxy, it was possibly ourselves in
         * proxy_detect
         */
        return OK;
    }

    /*
     * XXX: since r->uri has been manipulated already we're not really
     * compliant with RFC1945 at this point.  But this probably isn't an
     * issue because this is a hybrid proxy/origin server.
     */

    for (i = 0; i < conf->aliases->nelts; i++) {
        len = alias_match(r->uri, ent[i].fake);

        if (len > 0) {
            r->filename = ap_pstrcat(r->pool, "proxy:", ent[i].real,
                                     r->uri + len, NULL);
            r->handler = "proxy-server";
            r->proxyreq = PROXY_PASS;
            return OK;
        }
    }
    return DECLINED;
}

/* -------------------------------------------------------------- */
/* Fixup the filename */

/*
 * Canonicalise the URL
 */
static int proxy_fixup(request_rec *r)
{
    char *url, *p;

    if (r->proxyreq == NOT_PROXY || strncmp(r->filename, "proxy:", 6) != 0)
        return DECLINED;

    url = &r->filename[6];

/* canonicalise each specific scheme */
    if (strncasecmp(url, "http:", 5) == 0)
        return ap_proxy_http_canon(r, url + 5, "http", DEFAULT_HTTP_PORT);
    else if (strncasecmp(url, "ftp:", 4) == 0)
        return ap_proxy_ftp_canon(r, url + 4);

    p = strchr(url, ':');
    if (p == NULL || p == url)
        return HTTP_BAD_REQUEST;

    return OK;                  /* otherwise; we've done the best we can */
}

static void proxy_init(server_rec *r, pool *p)
{
    ap_proxy_garbage_init(r, p);
}



/* Send a redirection if the request contains a hostname which is not */
/* fully qualified, i.e. doesn't have a domain name appended. Some proxy */
/* servers like Netscape's allow this and access hosts from the local */
/* domain in this case. I think it is better to redirect to a FQDN, since */
/* these will later be found in the bookmarks files. */
/* The "ProxyDomain" directive determines what domain will be appended */
static int proxy_needsdomain(request_rec *r, const char *url, const char *domain)
{
    char *nuri;
    const char *ref;

    /* We only want to worry about GETs */
    if (r->proxyreq == NOT_PROXY || r->method_number != M_GET || !r->parsed_uri.hostname)
        return DECLINED;

    /* If host does contain a dot already, or it is "localhost", decline */
    if (strchr(r->parsed_uri.hostname, '.') != NULL
        || strcasecmp(r->parsed_uri.hostname, "localhost") == 0)
        return DECLINED;        /* host name has a dot already */

    ref = ap_table_get(r->headers_in, "Referer");

    /* Reassemble the request, but insert the domain after the host name */
    /* Note that the domain name always starts with a dot */
    r->parsed_uri.hostname = ap_pstrcat(r->pool, r->parsed_uri.hostname,
                                        domain, NULL);
    nuri = ap_unparse_uri_components(r->pool,
                                     &r->parsed_uri,
                                     UNP_REVEALPASSWORD);

    ap_table_set(r->headers_out, "Location", nuri);
    ap_log_rerror(APLOG_MARK, APLOG_INFO | APLOG_NOERRNO, r,
                  "Domain missing: %s sent to %s%s%s", r->uri,
                  ap_unparse_uri_components(r->pool, &r->parsed_uri,
                                            UNP_OMITUSERINFO),
                  ref ? " from " : "", ref ? ref : "");

    return HTTP_MOVED_PERMANENTLY;
}

/* -------------------------------------------------------------- */
/* Invoke handler */

static int proxy_handler(request_rec *r)
{
    char *url, *scheme, *p;
    void *sconf = r->server->module_config;
    proxy_server_conf *conf =
    (proxy_server_conf *)ap_get_module_config(sconf, &proxy_module);
    array_header *proxies = conf->proxies;
    struct proxy_remote *ents = (struct proxy_remote *) proxies->elts;
    int i, rc;
    cache_req *cr;
    int direct_connect = 0;
    const char *maxfwd_str;

    if (r->proxyreq == NOT_PROXY || strncmp(r->filename, "proxy:", 6) != 0)
        return DECLINED;

    if (r->method_number == M_TRACE &&
        (maxfwd_str = ap_table_get(r->headers_in, "Max-Forwards")) != NULL) {
        long maxfwd = ap_strtol(maxfwd_str, NULL, 10);
        if (maxfwd < 1) {
            int access_status;
            r->proxyreq = NOT_PROXY;
            if ((access_status = ap_send_http_trace(r)))
                ap_die(access_status, r);
            else
                ap_finalize_request_protocol(r);
            return OK;
        }
        ap_table_setn(r->headers_in, "Max-Forwards",
                ap_psprintf(r->pool, "%ld", (maxfwd > 0) ? maxfwd - 1 : 0));
    }

    if ((rc = ap_setup_client_block(r, REQUEST_CHUNKED_ERROR)))
        return rc;

    url = r->filename + 6;
    p = strchr(url, ':');
    if (p == NULL)
        return HTTP_BAD_REQUEST;

    /* Try serve the request from the cache. If we succeed, we leave. */
    rc = ap_proxy_cache_check(r, url, &conf->cache, &cr);
    if (rc != DECLINED)
        return rc;

    /* If the host doesn't have a domain name, add one and redirect. */
    if (conf->domain != NULL) {
        rc = proxy_needsdomain(r, url, conf->domain);
        if (ap_is_HTTP_REDIRECT(rc))
            return HTTP_MOVED_PERMANENTLY;
    }

    *p = '\0';
    scheme = ap_pstrdup(r->pool, url);
    *p = ':';

    /* Check URI's destination host against NoProxy hosts */
    /* Bypass ProxyRemote server lookup if configured as NoProxy */
    /* we only know how to handle communication to a proxy via http */
    /* if (strcasecmp(scheme, "http") == 0) */
    {
        int ii;
        struct dirconn_entry *list = (struct dirconn_entry *)conf->dirconn->elts;

        for (direct_connect = ii = 0; ii < conf->dirconn->nelts && !direct_connect; ii++) {
            direct_connect = list[ii].matcher(&list[ii], r);
        }
#if DEBUGGING
        ap_log_rerror(APLOG_MARK, APLOG_DEBUG | APLOG_NOERRNO, r,
                    (direct_connect) ? "NoProxy for %s" : "UseProxy for %s",
                      r->uri);
#endif
    }

/* firstly, try a proxy, unless a NoProxy directive is active */

    if (!direct_connect)
        for (i = 0; i < proxies->nelts; i++) {
            p = strchr(ents[i].scheme, ':');    /* is it a partial URL? */
            if (strcmp(ents[i].scheme, "*") == 0 ||
                (p == NULL && strcasecmp(scheme, ents[i].scheme) == 0) ||
                (p != NULL &&
            strncasecmp(url, ents[i].scheme, strlen(ents[i].scheme)) == 0)) {
                /*
                 * CONNECT is a special method that bypasses the normal proxy
                 * code.
                 */
                if (r->method_number == M_CONNECT)
                    rc = ap_proxy_connect_handler(r, cr, url, ents[i].hostname,
                                                  ents[i].port);
/* we only know how to handle communication to a proxy via http */
                else if (strcasecmp(ents[i].protocol, "http") == 0)
                    rc = ap_proxy_http_handler(r, cr, url, ents[i].hostname,
                                               ents[i].port);
                else
                    rc = DECLINED;

                /* an error or success */
                if (rc != DECLINED && rc != HTTP_BAD_GATEWAY)
                    return rc;
                /* we failed to talk to the upstream proxy */
            }
        }

    /* otherwise, try it direct */
    /* N.B. what if we're behind a firewall, where we must use a proxy or
     * give up??
     */

    /* handle the scheme */
    if (r->method_number == M_CONNECT) {
        return ap_proxy_connect_handler(r, cr, url, NULL, 0);
    }
    if (strcasecmp(scheme, "http") == 0) {
        return ap_proxy_http_handler(r, cr, url, NULL, 0);
    }
    if (strcasecmp(scheme, "ftp") == 0) {
        return ap_proxy_ftp_handler(r, cr, url);
    }
    else {
        ap_log_rerror(APLOG_MARK, APLOG_WARNING | APLOG_NOERRNO, r,
                    "proxy: No protocol handler was valid for the URL %s. "
                    "If you are using a DSO version of mod_proxy, make sure "
                    "the proxy submodules are included in the configuration "
                    "using LoadModule.", r->uri);
        return HTTP_FORBIDDEN;
    }
}

/* -------------------------------------------------------------- */
/* Setup configurable data */

static void *
     create_proxy_config(pool *p, server_rec *s)
{
    proxy_server_conf *ps = ap_pcalloc(p, sizeof(proxy_server_conf));

    ps->proxies = ap_make_array(p, 10, sizeof(struct proxy_remote));
    ps->aliases = ap_make_array(p, 10, sizeof(struct proxy_alias));
    ps->raliases = ap_make_array(p, 10, sizeof(struct proxy_alias));
    ps->noproxies = ap_make_array(p, 10, sizeof(struct noproxy_entry));
    ps->dirconn = ap_make_array(p, 10, sizeof(struct dirconn_entry));
    ps->nocaches = ap_make_array(p, 10, sizeof(struct nocache_entry));
    ps->allowed_connect_ports = ap_make_array(p, 10, sizeof(int));
    ps->domain = NULL;
    ps->viaopt = via_off;       /* initially backward compatible with 1.3.1 */
    ps->viaopt_set = 0;         /* 0 means default */
    ps->req = 0;
    ps->req_set = 0;
    ps->recv_buffer_size = 0;   /* this default was left unset for some
                                 * reason */
    ps->recv_buffer_size_set = 0;
    ps->io_buffer_size = IOBUFSIZE;
    ps->io_buffer_size_set = 0;

    ps->cache.root = NULL;
    ps->cache.space = DEFAULT_CACHE_SPACE;
    ps->cache.space_set = 0;
    ps->cache.maxexpire = DEFAULT_CACHE_MAXEXPIRE;
    ps->cache.maxexpire_set = 0;
    ps->cache.defaultexpire = DEFAULT_CACHE_EXPIRE;
    ps->cache.defaultexpire_set = 0;
    ps->cache.lmfactor = DEFAULT_CACHE_LMFACTOR;
    ps->cache.lmfactor_set = 0;
    ps->cache.gcinterval = DEFAULT_CACHE_GCINTERVAL;
    ps->cache.gcinterval_set = 1;
    /* at these levels, the cache can have 2^18 directories (256,000)  */
    ps->cache.dirlevels = 3;
    ps->cache.dirlevels_set = 0;
    ps->cache.dirlength = 1;
    ps->cache.dirlength_set = 0;
    ps->cache.cache_completion = (float)DEFAULT_CACHE_COMPLETION;
    ps->cache.cache_completion_set = 0;

    return ps;
}

static void *
     merge_proxy_config(pool *p, void *basev,
                             void *overridesv)
{
    proxy_server_conf *ps = ap_pcalloc(p, sizeof(proxy_server_conf));
    proxy_server_conf *base = (proxy_server_conf *)basev;
    proxy_server_conf *overrides = (proxy_server_conf *)overridesv;

    ps->proxies = ap_append_arrays(p, base->proxies, overrides->proxies);
    ps->aliases = ap_append_arrays(p, base->aliases, overrides->aliases);
    ps->raliases = ap_append_arrays(p, base->raliases, overrides->raliases);
    ps->noproxies = ap_append_arrays(p, base->noproxies, overrides->noproxies);
    ps->dirconn = ap_append_arrays(p, base->dirconn, overrides->dirconn);
    ps->nocaches = ap_append_arrays(p, base->nocaches, overrides->nocaches);
    ps->allowed_connect_ports = ap_append_arrays(p, base->allowed_connect_ports, overrides->allowed_connect_ports);

    ps->domain = (overrides->domain == NULL) ? base->domain : overrides->domain;
    ps->viaopt = (overrides->viaopt_set == 0) ? base->viaopt : overrides->viaopt;
    ps->req = (overrides->req_set == 0) ? base->req : overrides->req;
    ps->recv_buffer_size = (overrides->recv_buffer_size_set == 0) ? base->recv_buffer_size : overrides->recv_buffer_size;
    ps->io_buffer_size = (overrides->io_buffer_size_set == 0) ? base->io_buffer_size : overrides->io_buffer_size;

    ps->cache.root = (overrides->cache.root == NULL) ? base->cache.root : overrides->cache.root;
    ps->cache.space = (overrides->cache.space_set == 0) ? base->cache.space : overrides->cache.space;
    ps->cache.maxexpire = (overrides->cache.maxexpire_set == 0) ? base->cache.maxexpire : overrides->cache.maxexpire;
    ps->cache.defaultexpire = (overrides->cache.defaultexpire_set == 0) ? base->cache.defaultexpire : overrides->cache.defaultexpire;
    ps->cache.lmfactor = (overrides->cache.lmfactor_set == 0) ? base->cache.lmfactor : overrides->cache.lmfactor;
    ps->cache.gcinterval = (overrides->cache.gcinterval_set == 0) ? base->cache.gcinterval : overrides->cache.gcinterval;
    /* at these levels, the cache can have 2^18 directories (256,000)  */
    ps->cache.dirlevels = (overrides->cache.dirlevels_set == 0) ? base->cache.dirlevels : overrides->cache.dirlevels;
    ps->cache.dirlength = (overrides->cache.dirlength_set == 0) ? base->cache.dirlength : overrides->cache.dirlength;
    ps->cache.cache_completion = (overrides->cache.cache_completion_set == 0) ? base->cache.cache_completion : overrides->cache.cache_completion;

    return ps;
}

static const char *
     add_proxy(cmd_parms *cmd, void *dummy, char *f, char *r)
{
    server_rec *s = cmd->server;
    proxy_server_conf *conf =
    (proxy_server_conf *)ap_get_module_config(s->module_config, &proxy_module);
    struct proxy_remote *new;
    char *p, *q;
    int port;

    p = strchr(r, ':');
    if (p == NULL || p[1] != '/' || p[2] != '/' || p[3] == '\0')
        return "ProxyRemote: Bad syntax for a remote proxy server";
    q = strchr(p + 3, ':');
    if (q != NULL) {
        if (sscanf(q + 1, "%u", &port) != 1 || port > 65535)
            return "ProxyRemote: Bad syntax for a remote proxy server (bad port number)";
        *q = '\0';
    }
    else
        port = -1;
    *p = '\0';
    if (strchr(f, ':') == NULL)
        ap_str_tolower(f);      /* lowercase scheme */
    ap_str_tolower(p + 3);      /* lowercase hostname */

    if (port == -1) {
        int i;
        for (i = 0; defports[i].scheme != NULL; i++)
            if (strcasecmp(defports[i].scheme, r) == 0)
                break;
        port = defports[i].port;
    }

    new = ap_push_array(conf->proxies);
    new->scheme = f;
    new->protocol = r;
    new->hostname = p + 3;
    new->port = port;
    return NULL;
}

static const char *
     add_pass(cmd_parms *cmd, void *dummy, char *f, char *r)
{
    server_rec *s = cmd->server;
    proxy_server_conf *conf =
    (proxy_server_conf *)ap_get_module_config(s->module_config, &proxy_module);
    struct proxy_alias *new;

    new = ap_push_array(conf->aliases);
    new->fake = f;
    new->real = r;
    return NULL;
}

static const char *
     add_pass_reverse(cmd_parms *cmd, void *dummy, char *f, char *r)
{
    server_rec *s = cmd->server;
    proxy_server_conf *conf;
    struct proxy_alias *new;

    conf = (proxy_server_conf *)ap_get_module_config(s->module_config,
                                                     &proxy_module);
    new = ap_push_array(conf->raliases);
    new->fake = f;
    new->real = r;
    return NULL;
}

static const char *
     set_proxy_exclude(cmd_parms *parms, void *dummy, char *arg)
{
    server_rec *s = parms->server;
    proxy_server_conf *conf =
    ap_get_module_config(s->module_config, &proxy_module);
    struct noproxy_entry *new;
    struct noproxy_entry *list = (struct noproxy_entry *) conf->noproxies->elts;
    struct hostent hp;
    int found = 0;
    int i;

    /* Don't duplicate entries */
    for (i = 0; i < conf->noproxies->nelts; i++) {
        if (strcasecmp(arg, list[i].name) == 0) /* ignore case for host names */
            found = 1;
    }

    if (!found) {
        new = ap_push_array(conf->noproxies);
        new->name = arg;
        /* Don't do name lookups on things that aren't dotted */
        if (strchr(arg, '.') != NULL && ap_proxy_host2addr(new->name, &hp) == NULL)
            /*
             * @@@FIXME: This copies only the first of (possibly many) IP
             * addrs
             */
            memcpy(&new->addr, hp.h_addr, sizeof(struct in_addr));
        else
            new->addr.s_addr = 0;
    }
    return NULL;
}

/*
 * Set the ports CONNECT can use
 */
static const char *
     set_allowed_ports(cmd_parms *parms, void *dummy, char *arg)
{
    server_rec *s = parms->server;
    proxy_server_conf *conf =
    ap_get_module_config(s->module_config, &proxy_module);
    int *New;

    if (!ap_isdigit(arg[0]))
        return "AllowCONNECT: port number must be numeric";

    New = ap_push_array(conf->allowed_connect_ports);
    *New = atoi(arg);
    return NULL;
}

/* Similar to set_proxy_exclude(), but defining directly connected hosts,
 * which should never be accessed via the configured ProxyRemote servers
 */
static const char *
     set_proxy_dirconn(cmd_parms *parms, void *dummy, char *arg)
{
    server_rec *s = parms->server;
    proxy_server_conf *conf =
    ap_get_module_config(s->module_config, &proxy_module);
    struct dirconn_entry *New;
    struct dirconn_entry *list = (struct dirconn_entry *)conf->dirconn->elts;
    int found = 0;
    int i;

    /* Don't duplicate entries */
    for (i = 0; i < conf->dirconn->nelts; i++) {
        if (strcasecmp(arg, list[i].name) == 0)
            found = 1;
    }

    if (!found) {
        New = ap_push_array(conf->dirconn);
        New->name = arg;
        New->hostentry = NULL;

        if (ap_proxy_is_ipaddr(New, parms->pool)) {
#if DEBUGGING
            fprintf(stderr, "Parsed addr %s\n", inet_ntoa(New->addr));
            fprintf(stderr, "Parsed mask %s\n", inet_ntoa(New->mask));
#endif
        }
        else if (ap_proxy_is_domainname(New, parms->pool)) {
            ap_str_tolower(New->name);
#if DEBUGGING
            fprintf(stderr, "Parsed domain %s\n", New->name);
#endif
        }
        else if (ap_proxy_is_hostname(New, parms->pool)) {
            ap_str_tolower(New->name);
#if DEBUGGING
            fprintf(stderr, "Parsed host %s\n", New->name);
#endif
        }
        else {
            ap_proxy_is_word(New, parms->pool);
#if DEBUGGING
            fprintf(stderr, "Parsed word %s\n", New->name);
#endif
        }
    }
    return NULL;
}

static const char *
     set_proxy_domain(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);

    if (arg[0] != '.')
        return "ProxyDomain: domain name must start with a dot.";

    psf->domain = arg;
    return NULL;
}

static const char *
     set_proxy_req(cmd_parms *parms, void *dummy, int flag)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);

    psf->req = flag;
    psf->req_set = 1;
    return NULL;
}


static const char *
     set_cache_size(cmd_parms *parms, char *struct_ptr, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    int val;

    if (sscanf(arg, "%d", &val) != 1)
        return "CacheSize value must be an integer (kBytes)";
    psf->cache.space = val;
    psf->cache.space_set = 1;
    return NULL;
}

static const char *
     set_cache_root(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);

    psf->cache.root = arg;

    return NULL;
}

static const char *
     set_cache_factor(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    double val;

    if (sscanf(arg, "%lg", &val) != 1)
        return "CacheLastModifiedFactor value must be a float";
    psf->cache.lmfactor = val;
    psf->cache.lmfactor_set = 1;

    return NULL;
}

static const char *
     set_cache_maxex(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    double val;

    if (sscanf(arg, "%lg", &val) != 1)
        return "CacheMaxExpire value must be a float";
    psf->cache.maxexpire = (int)(val * (double)SEC_ONE_HR);
    psf->cache.maxexpire_set = 1;
    return NULL;
}

static const char *
     set_cache_defex(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    double val;

    if (sscanf(arg, "%lg", &val) != 1)
        return "CacheDefaultExpire value must be a float";
    psf->cache.defaultexpire = (int)(val * (double)SEC_ONE_HR);
    psf->cache.defaultexpire_set = 1;
    return NULL;
}

static const char *
     set_cache_gcint(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    double val;

    if (sscanf(arg, "%lg", &val) != 1)
        return "CacheGcInterval value must be a float";
    psf->cache.gcinterval = (int)(val * (double)SEC_ONE_HR);
    psf->cache.gcinterval_set = 1;
    return NULL;
}

static const char *
     set_cache_dirlevels(cmd_parms *parms, char *struct_ptr, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    int val;

    val = atoi(arg);
    if (val < 1)
        return "CacheDirLevels value must be an integer greater than 0";
    if (val * psf->cache.dirlength > CACHEFILE_LEN)
        return "CacheDirLevels*CacheDirLength value must not be higher than 20";
    psf->cache.dirlevels = val;
    psf->cache.dirlevels_set = 1;
    return NULL;
}

static const char *
     set_cache_dirlength(cmd_parms *parms, char *struct_ptr, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    int val;

    val = atoi(arg);
    if (val < 1)
        return "CacheDirLength value must be an integer greater than 0";
    if (val * psf->cache.dirlevels > CACHEFILE_LEN)
        return "CacheDirLevels*CacheDirLength value must not be higher than 20";
    psf->cache.dirlength = val;
    psf->cache.dirlength_set = 1;
    return NULL;
}

static const char *
     set_cache_exclude(cmd_parms *parms, void *dummy, char *arg)
{
    server_rec *s = parms->server;
    proxy_server_conf *conf =
    ap_get_module_config(s->module_config, &proxy_module);
    struct nocache_entry *new;
    struct nocache_entry *list = (struct nocache_entry *) conf->nocaches->elts;
    struct hostent hp;
    int found = 0;
    int i;

    /* Don't duplicate entries */
    for (i = 0; i < conf->nocaches->nelts; i++) {
        if (strcasecmp(arg, list[i].name) == 0) /* ignore case for host names */
            found = 1;
    }

    if (!found) {
        new = ap_push_array(conf->nocaches);
        new->name = arg;
        /* Don't do name lookups on things that aren't dotted */
        if (strchr(arg, '.') != NULL && ap_proxy_host2addr(new->name, &hp) == NULL)
            /*
             * @@@FIXME: This copies only the first of (possibly many) IP
             * addrs
             */
            memcpy(&new->addr, hp.h_addr, sizeof(struct in_addr));
        else
            new->addr.s_addr = 0;
    }
    return NULL;
}

static const char *
     set_recv_buffer_size(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    int s = atoi(arg);
    if (s < 512 && s != 0) {
        return "ProxyReceiveBufferSize must be >= 512 bytes, or 0 for system default.";
    }

    psf->recv_buffer_size = s;
    psf->recv_buffer_size_set = 1;
    return NULL;
}

static const char *
     set_io_buffer_size(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    long s = atol(arg);

    psf->io_buffer_size = ((s > IOBUFSIZE) ? s : IOBUFSIZE);
    psf->io_buffer_size_set = 1;
    return NULL;
}

static const char *
     set_cache_completion(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);
    int s = atoi(arg);
    if (s > 100 || s < 0) {
        return "CacheForceCompletion must be <= 100 percent, "
            "or 0 for system default.";
    }

    if (s > 0)
        psf->cache.cache_completion = ((float)s / 100);

    psf->cache.cache_completion_set = 1;
    return NULL;
}

static const char *
     set_via_opt(cmd_parms *parms, void *dummy, char *arg)
{
    proxy_server_conf *psf =
    ap_get_module_config(parms->server->module_config, &proxy_module);

    if (strcasecmp(arg, "Off") == 0)
        psf->viaopt = via_off;
    else if (strcasecmp(arg, "On") == 0)
        psf->viaopt = via_on;
    else if (strcasecmp(arg, "Block") == 0)
        psf->viaopt = via_block;
    else if (strcasecmp(arg, "Full") == 0)
        psf->viaopt = via_full;
    else {
        return "ProxyVia must be one of: "
            "off | on | full | block";
    }

    psf->viaopt_set = 1;
    return NULL;
}

static const handler_rec proxy_handlers[] =
{
    {"proxy-server", proxy_handler},
    {NULL}
};

static const command_rec proxy_cmds[] =
{
    {"ProxyRequests", set_proxy_req, NULL, RSRC_CONF, FLAG,
    "on if the true proxy requests should be accepted"},
    {"ProxyRemote", add_proxy, NULL, RSRC_CONF, TAKE2,
    "a scheme, partial URL or '*' and a proxy server"},
    {"ProxyPass", add_pass, NULL, RSRC_CONF, TAKE2,
    "a virtual path and a URL"},
    {"ProxyPassReverse", add_pass_reverse, NULL, RSRC_CONF, TAKE2,
    "a virtual path and a URL for reverse proxy behaviour"},
    {"ProxyBlock", set_proxy_exclude, NULL, RSRC_CONF, ITERATE,
    "A list of names, hosts or domains to which the proxy will not connect"},
    {"ProxyReceiveBufferSize", set_recv_buffer_size, NULL, RSRC_CONF, TAKE1,
    "Receive buffer size for outgoing HTTP and FTP connections in bytes"},
    {"ProxyIOBufferSize", set_io_buffer_size, NULL, RSRC_CONF, TAKE1,
    "IO buffer size for outgoing HTTP and FTP connections in bytes"},
    {"NoProxy", set_proxy_dirconn, NULL, RSRC_CONF, ITERATE,
    "A list of domains, hosts, or subnets to which the proxy will connect directly"},
    {"ProxyDomain", set_proxy_domain, NULL, RSRC_CONF, TAKE1,
    "The default intranet domain name (in absence of a domain in the URL)"},
    {"AllowCONNECT", set_allowed_ports, NULL, RSRC_CONF, ITERATE,
    "A list of ports which CONNECT may connect to"},
    {"CacheRoot", set_cache_root, NULL, RSRC_CONF, TAKE1,
    "The directory to store cache files"},
    {"CacheSize", set_cache_size, NULL, RSRC_CONF, TAKE1,
    "The maximum disk space used by the cache in Kb"},
    {"CacheMaxExpire", set_cache_maxex, NULL, RSRC_CONF, TAKE1,
    "The maximum time in hours to cache a document"},
    {"CacheDefaultExpire", set_cache_defex, NULL, RSRC_CONF, TAKE1,
    "The default time in hours to cache a document"},
    {"CacheLastModifiedFactor", set_cache_factor, NULL, RSRC_CONF, TAKE1,
    "The factor used to estimate Expires date from LastModified date"},
    {"CacheGcInterval", set_cache_gcint, NULL, RSRC_CONF, TAKE1,
    "The interval between garbage collections, in hours"},
    {"CacheDirLevels", set_cache_dirlevels, NULL, RSRC_CONF, TAKE1,
    "The number of levels of subdirectories in the cache"},
    {"CacheDirLength", set_cache_dirlength, NULL, RSRC_CONF, TAKE1,
    "The number of characters in subdirectory names"},
    {"NoCache", set_cache_exclude, NULL, RSRC_CONF, ITERATE,
    "A list of names, hosts or domains for which caching is *not* provided"},
    {"CacheForceCompletion", set_cache_completion, NULL, RSRC_CONF, TAKE1,
    "Force a http cache completion after this percentage is loaded"},
    {"ProxyVia", set_via_opt, NULL, RSRC_CONF, TAKE1,
    "Configure Via: proxy header header to one of: on | off | block | full"},
    {NULL}
};

module MODULE_VAR_EXPORT proxy_module =
{
    STANDARD_MODULE_STUFF,
    proxy_init,                 /* initializer */
    NULL,                       /* create per-directory config structure */
    NULL,                       /* merge per-directory config structures */
    create_proxy_config,        /* create per-server config structure */
    merge_proxy_config,         /* merge per-server config structures */
    proxy_cmds,                 /* command table */
    proxy_handlers,             /* handlers */
    proxy_trans,                /* translate_handler */
    NULL,                       /* check_user_id */
    NULL,                       /* check auth */
    NULL,                       /* check access */
    NULL,                       /* type_checker */
    proxy_fixup,                /* pre-run fixups */
    NULL,                       /* logger */
    NULL,                       /* header parser */
    NULL,                       /* child_init */
    NULL,                       /* child_exit */
    proxy_detect                /* post read-request */
};
