Ziele Untersuchung
mit Columbo Integrität von
Datenbanken Interaktion und
Portierbarkeit Ergonomie der
Schnittstellen

Angebot Produkte Projekt Beratung

Mittel Analytik Modellierung Sprachen Algebra Logik Hardware Denken Kreativität

Zusammenhänge Gesellschaft Wirtschaft Branche Firma


products/sources/formale Sprachen/C/Apache/modules/metadata/ (Apache Software Stiftung Version 2.4.65^©) Datei vom 6.9.2015 mit Größe 10 kB

Quelle mod_ident.c Sprache: C

/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements.  See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/

/*
* mod_ident: Handle RFC 1413 ident request
* obtained from rfc1413.c
*
* rfc1413() speaks a common subset of the RFC 1413, AUTH, TAP and IDENT
* protocols. The code queries an RFC 1413 etc. compatible daemon on a remote
* host to look up the owner of a connection. The information should not be
* used for authentication purposes. This routine intercepts alarm signals.
*
* Author: Wietse Venema, Eindhoven University of Technology,
* The Netherlands.
*/

/* Some small additions for Apache --- ditch the "sccsid" var if
* compiling with gcc (it *has* changed), include ap_config.h for the
* prototypes it defines on at least one system (SunlOSs) which has
* them missing from the standard header files, and one minor change
* below (extra parens around assign "if (foo = bar) ..." to shut up
* gcc -Wall).
*/

/* Rewritten by David Robinson */

#include "apr.h"
#include "apr_network_io.h"
#include "apr_strings.h"
#include "apr_optional.h"

#define APR_WANT_STDIO
#define APR_WANT_STRFUNC
#include "apr_want.h"

#include "httpd.h"              /* for server_rec, conn_rec, etc. */
#include "http_config.h"
#include "http_core.h"
#include "http_log.h"           /* for aplog_error */
#include "util_ebcdic.h"

/* Whether we should enable rfc1413 identity checking */
#ifndef DEFAULT_RFC1413
#define DEFAULT_RFC1413    0
#endif

#define RFC1413_UNSET 2

/* request timeout (sec) */
#ifndef RFC1413_TIMEOUT
#define RFC1413_TIMEOUT   30
#endif

/* Local stuff. */

/* Semi-well-known port */
#define RFC1413_PORT     113

/* maximum allowed length of userid */
#define RFC1413_USERLEN  512

/* rough limit on the amount of data we accept. */
#define RFC1413_MAXDATA 1000

/* default username, if it could not determined */
#define FROM_UNKNOWN  "unknown"

typedef struct {
    int do_rfc1413;
    int timeout_unset;
    apr_time_t timeout;
} ident_config_rec;

static apr_status_t rfc1413_connect(apr_socket_t **newsock, conn_rec *conn,
                                    server_rec *srv, apr_time_t timeout)
{
    apr_status_t rv;
    apr_sockaddr_t *localsa, *destsa;

    if ((rv = apr_sockaddr_info_get(&localsa, conn->local_ip, APR_UNSPEC,
                              0, /* ephemeral port */
                              0, conn->pool)) != APR_SUCCESS) {
        /* This should not fail since we have a numeric address string
         * as the host. */
        ap_log_error(APLOG_MARK, APLOG_CRIT, rv, srv, APLOGNO(01492)
                     "rfc1413: apr_sockaddr_info_get(%s) failed",
                     conn->local_ip);
        return rv;
    }

    if ((rv = apr_sockaddr_info_get(&destsa, conn->client_ip,
                              localsa->family, /* has to match */
                              RFC1413_PORT, 0, conn->pool)) != APR_SUCCESS) {
        /* This should not fail since we have a numeric address string
         * as the host. */
        ap_log_error(APLOG_MARK, APLOG_CRIT, rv, srv, APLOGNO(01493)
                     "rfc1413: apr_sockaddr_info_get(%s) failed",
                     conn->client_ip);
        return rv;
    }

    if ((rv = apr_socket_create(newsock,
                                localsa->family, /* has to match */
                                SOCK_STREAM, 0, conn->pool)) != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_CRIT, rv, srv, APLOGNO(01494)
                     "rfc1413: error creating query socket");
        return rv;
    }

    if ((rv = apr_socket_timeout_set(*newsock, timeout)) != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_CRIT, rv, srv, APLOGNO(01495)
                     "rfc1413: error setting query socket timeout");
        apr_socket_close(*newsock);
        return rv;
    }

/*
* Bind the local and remote ends of the query socket to the same
* IP addresses as the connection under investigation. We go
* through all this trouble because the local or remote system
* might have more than one network address. The RFC1413 etc.
* client sends only port numbers; the server takes the IP
* addresses from the query socket.
*/

    if ((rv = apr_socket_bind(*newsock, localsa)) != APR_SUCCESS) {
        ap_log_error(APLOG_MARK, APLOG_CRIT, rv, srv, APLOGNO(01496)
                     "rfc1413: Error binding query socket to local port");
        apr_socket_close(*newsock);
        return rv;
    }

/*
* errors from connect usually imply the remote machine doesn't support
* the service; don't log such an error
*/
    if ((rv = apr_socket_connect(*newsock, destsa)) != APR_SUCCESS) {
        apr_socket_close(*newsock);
        return rv;
    }

    return APR_SUCCESS;
}

static apr_status_t rfc1413_query(apr_socket_t *sock, conn_rec *conn,
                                  server_rec *srv)
{
    apr_port_t rmt_port, our_port;
    apr_port_t sav_rmt_port, sav_our_port;
    apr_size_t i;
    char *cp;
    char buffer[RFC1413_MAXDATA + 1];
    char user[RFC1413_USERLEN + 1];     /* XXX */
    apr_size_t buflen;

    sav_our_port = conn->local_addr->port;
    sav_rmt_port = conn->client_addr->port;

    /* send the data */
    buflen = apr_snprintf(buffer, sizeof(buffer), "%hu,%hu\r\n", sav_rmt_port,
                          sav_our_port);
    ap_xlate_proto_to_ascii(buffer, buflen);

    /* send query to server. Handle short write. */
    i = 0;
    while (i < buflen) {
        apr_size_t j = strlen(buffer + i);
        apr_status_t status;
        status  = apr_socket_send(sock, buffer+i, &j);
        if (status != APR_SUCCESS) {
            ap_log_error(APLOG_MARK, APLOG_CRIT, status, srv, APLOGNO(01497)
                         "write: rfc1413: error sending request");
            return status;
        }
        else if (j > 0) {
            i+=j;
        }
    }

    /*
     * Read response from server. - the response should be newline
     * terminated according to rfc - make sure it doesn't stomp its
     * way out of the buffer.
     */

    i = 0;
    memset(buffer, '\0', sizeof(buffer));
    /*
     * Note that the strchr function below checks for \012 instead of '\n'
     * this allows it to work on both ASCII and EBCDIC machines.
     */
    while ((cp = strchr(buffer, '\012')) == NULL && i < sizeof(buffer) - 1) {
        apr_size_t j = sizeof(buffer) - 1 - i;
        apr_status_t status;
        status = apr_socket_recv(sock, buffer+i, &j);
        if (status != APR_SUCCESS) {
            ap_log_error(APLOG_MARK, APLOG_CRIT, status, srv, APLOGNO(01498)
                         "read: rfc1413: error reading response");
            return status;
        }
        else if (j > 0) {
            i+=j;
        }
        else if (status == APR_SUCCESS && j == 0) {
            /* Oops... we ran out of data before finding newline */
            return APR_EINVAL;
        }
    }

/* RFC1413_USERLEN = 512 */
    ap_xlate_proto_from_ascii(buffer, i);
    if (sscanf(buffer, "%hu , %hu : USERID :%*[^:]:%512s", &rmt_port, &our_port,
               user) != 3 || sav_rmt_port != rmt_port
        || sav_our_port != our_port)
        return APR_EINVAL;

    /*
     * Strip trailing carriage return. It is part of the
     * protocol, not part of the data.
     */

    if ((cp = strchr(user, '\r')))
        *cp = '\0';

    conn->remote_logname = apr_pstrdup(conn->pool, user);

    return APR_SUCCESS;
}

static const char *set_idcheck(cmd_parms *cmd, void *d_, int arg)
{
    ident_config_rec *d = d_;

    d->do_rfc1413 = arg ? 1 : 0;
    return NULL;
}

static const char *set_timeout(cmd_parms *cmd, void *d_, const char *arg)
{
    ident_config_rec *d = d_;

    d->timeout = apr_time_from_sec(atoi(arg));
    d->timeout_unset = 0;
    return NULL;
}

static void *create_ident_dir_config(apr_pool_t *p, char *d)
{
    ident_config_rec *conf = apr_palloc(p, sizeof(*conf));

    conf->do_rfc1413 = DEFAULT_RFC1413 | RFC1413_UNSET;
    conf->timeout = apr_time_from_sec(RFC1413_TIMEOUT);
    conf->timeout_unset = 1;

    return (void *)conf;
}

static void *merge_ident_dir_config(apr_pool_t *p, void *old_, void *new_)
{
    ident_config_rec *conf = (ident_config_rec *)apr_pcalloc(p, sizeof(*conf));
    ident_config_rec *old = (ident_config_rec *) old_;
    ident_config_rec *new = (ident_config_rec *) new_;

    conf->timeout = new->timeout_unset
                        ? old->timeout
                        : new->timeout;

    conf->do_rfc1413 = new->do_rfc1413 & RFC1413_UNSET
                           ? old->do_rfc1413
                           : new->do_rfc1413;

    return (void *)conf;
}

static const command_rec ident_cmds[] =
{
    AP_INIT_FLAG("IdentityCheck", set_idcheck, NULL, RSRC_CONF|ACCESS_CONF,
                 "Enable identd (RFC 1413) user lookups - SLOW"),
    AP_INIT_TAKE1("IdentityCheckTimeout", set_timeout, NULL,
                  RSRC_CONF|ACCESS_CONF,
                  "Identity check (RFC 1413) timeout duration (sec)"),
    {NULL}
};

module AP_MODULE_DECLARE_DATA ident_module;

/*
* Optional function for the core to the actual ident request
*/
static const char *ap_ident_lookup(request_rec *r)
{
    ident_config_rec *conf;
    apr_socket_t *sock;
    apr_status_t rv;
    conn_rec *conn = r->connection;
    server_rec *srv = r->server;

    conf = ap_get_module_config(r->per_dir_config, &ident_module);

    /* return immediately if ident requests are disabled */
    if (!(conf->do_rfc1413 & ~RFC1413_UNSET)) {
        return NULL;
    }

    rv = rfc1413_connect(&sock, conn, srv, conf->timeout);
    if (rv == APR_SUCCESS) {
        rv = rfc1413_query(sock, conn, srv);
        apr_socket_close(sock);
    }
    if (rv != APR_SUCCESS) {
        conn->remote_logname = FROM_UNKNOWN;
    }

    return (const char *)conn->remote_logname;
}

static void register_hooks(apr_pool_t *p)
{
    APR_REGISTER_OPTIONAL_FN(ap_ident_lookup);
}

AP_DECLARE_MODULE(ident) =
{
    STANDARD20_MODULE_STUFF,
    create_ident_dir_config,       /* dir config creater */
    merge_ident_dir_config,        /* dir merger --- default is to override */
    NULL,                          /* server config */
    NULL,                          /* merge server config */
    ident_cmds,                    /* command apr_table_t */
    register_hooks                 /* register hooks */
};

quality96%

¤ Dauer der Verarbeitung: 0.33 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.