rfc1413.c revision 333d217f9ee70eb89cb5d5a30bf08a0032f571ff
/* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 2000 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
* Portions of this software are based upon public domain software
* originally written at the National Center for Supercomputing Applications,
* University of Illinois, Urbana-Champaign.
*/
/* TODO - put timeouts back in */
/*
* 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.
*
* Diagnostics are reported through syslog(3).
*
* 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 "ap_config.h"
#include "httpd.h" /* for server_rec, conn_rec, etc. */
#include "http_log.h" /* for aplog_error */
#include "rfc1413.h"
#include "http_main.h" /* set_callback_and_alarm */
#include "util_ebcdic.h"
#include "apr_network_io.h"
#ifdef HAVE_STRING_H
#include <string.h>
#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
#ifndef RFC1413_TIMEOUT
#define RFC1413_TIMEOUT 30
#endif
#define ANY_PORT 0 /* Any old port will do */
#define FROM_UNKNOWN "unknown"
int ap_rfc1413_timeout = RFC1413_TIMEOUT; /* Global so it can be changed */
/* bind_connect - bind both ends of a socket */
/* Ambarish fix this. Very broken */
static int get_rfc1413(apr_socket_t *sock, const char *local_ip,
const char *rmt_ip,
char user[RFC1413_USERLEN+1], server_rec *srv)
{
unsigned int rmt_port, our_port;
unsigned int sav_rmt_port, sav_our_port;
apr_status_t status;
int i;
char *cp;
char buffer[RFC1413_MAXDATA + 1];
int buflen;
#ifdef CHARSET_EBCDIC
apr_size_t inbytes_left, outbytes_left;
#endif
/*
* 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.
*/
apr_set_local_port(sock, ANY_PORT);
apr_set_local_ipaddr(sock, local_ip);
if ((status = apr_bind(sock)) != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_CRIT, status, srv,
"bind: rfc1413: Error binding to local port");
return -1;
}
/*
* errors from connect usually imply the remote machine doesn't support
* the service
*/
apr_set_remote_port(sock, RFC1413_PORT);
apr_set_remote_ipaddr(sock, rmt_ip);
if (apr_connect(sock, NULL) != APR_SUCCESS)
return -1;
apr_get_local_port(&sav_our_port, sock);
apr_get_remote_port(&sav_rmt_port, sock);
/* send the data */
buflen = apr_snprintf(buffer, sizeof(buffer), "%u,%u\r\n", sav_rmt_port,
sav_our_port);
#ifdef CHARSET_EBCDIC
inbytes_left = outbytes_left = buflen;
apr_xlate_conv_buffer(ap_hdrs_to_ascii, buffer, &inbytes_left,
buffer, &outbytes_left);
#endif
/* send query to server. Handle short write. */
i = 0;
while(i < strlen(buffer)) {
apr_ssize_t j = strlen(buffer + i);
apr_status_t status;
status = apr_send(sock, buffer+i, &j);
if (status != APR_SUCCESS && apr_canonical_error(status) != APR_EINTR) {
ap_log_error(APLOG_MARK, APLOG_CRIT, status, srv,
"write: rfc1413: error sending request");
return -1;
}
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 it's
* 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_ssize_t j = sizeof(buffer) - 1 - i;
apr_status_t status;
status = apr_recv(sock, buffer+i, &j);
if (status != APR_SUCCESS && apr_canonical_error(status) != APR_EINTR) {
ap_log_error(APLOG_MARK, APLOG_CRIT, status, srv,
"read: rfc1413: error reading response");
return -1;
}
else if (j > 0) {
i+=j;
}
else if (status == APR_SUCCESS && j == 0) {
/* Oops... we ran out of data before finding newline */
return -1;
}
}
/* RFC1413_USERLEN = 512 */
#ifdef CHARSET_EBCDIC
inbytes_left = outbytes_left = i;
apr_xlate_conv_buffer(ap_hdrs_from_ascii, buffer, &inbytes_left,
buffer, &outbytes_left);
#endif
if (sscanf(buffer, "%u , %u : USERID :%*[^:]:%512s", &rmt_port, &our_port,
user) != 3 || sav_rmt_port != rmt_port
|| sav_our_port != our_port)
return -1;
/*
* Strip trailing carriage return. It is part of the
* protocol, not part of the data.
*/
if ((cp = strchr(user, '\r')))
*cp = '\0';
return 0;
}
/* rfc1413 - return remote user name, given socket structures */
char *ap_rfc1413(conn_rec *conn, server_rec *srv)
{
apr_status_t status;
static char user[RFC1413_USERLEN + 1]; /* XXX */
static char *result;
static apr_socket_t *sock;
result = FROM_UNKNOWN;
if ((status = apr_create_tcp_socket(&sock, conn->pool)) != APR_SUCCESS) {
ap_log_error(APLOG_MARK, APLOG_CRIT, status, srv,
"socket: rfc1413: error creating socket");
conn->remote_logname = result;
}
if (get_rfc1413(sock, conn->local_ip, conn->remote_ip, user, srv) >= 0)
result = user;
apr_close_socket(sock);
conn->remote_logname = result;
return conn->remote_logname;
}