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/*
* appl/sample/sserver/sserver.c
*
* Copyright 1990,1991 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
*
* Sample Kerberos v5 server.
*
* sample_server:
* A sample Kerberos server, which reads an AP_REQ from a TCP socket,
* decodes it, and writes back the results (in ASCII) to the client.
*
* Usage:
* sample_server servername
*
* file descriptor 0 (zero) should be a socket connected to the requesting
* client (this will be correct if this server is started by inetd).
*/
#include "krb5.h"
#include "com_err.h"
#include <stdio.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <syslog.h>
#include "../sample.h"
extern krb5_deltat krb5_clockskew;
#define DEBUG
void
main(argc, argv)
int argc;
char *argv[];
{
krb5_context context;
struct sockaddr_in peername;
krb5_address peeraddr;
int namelen = sizeof(peername);
int sock = 0; /* incoming connection fd */
krb5_data recv_data;
short xmitlen;
krb5_error_code retval;
krb5_principal server, client;
char repbuf[BUFSIZ];
char *cname;
krb5_init_context(&context);
krb5_init_ets(context);
/* open a log connection */
openlog("sserver", 0, LOG_DAEMON);
if (retval = krb5_sname_to_principal(context, NULL, SAMPLE_SERVICE,
KRB5_NT_SRV_HST, &server)) {
syslog(LOG_ERR, "while generating service name (%s): %s",
SAMPLE_SERVICE, error_message(retval));
exit(1);
}
/*
* If user specified a port, then listen on that port; otherwise,
* assume we've been started out of inetd.
*/
if (argc > 1) {
int acc;
struct sockaddr_in sin;
if ((sock = socket(PF_INET, SOCK_STREAM, 0)) < 0) {
syslog(LOG_ERR, "socket: %m");
exit(3);
}
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = 0;
sin.sin_port = htons(atoi(argv[1]));
if (bind(sock, &sin, sizeof(sin))) {
syslog(LOG_ERR, "bind: %m");
exit(3);
}
if (listen(sock, 1) == -1) {
syslog(LOG_ERR, "listen: %m");
exit(3);
}
if ((acc = accept(sock, (struct sockaddr *)&peername, &namelen)) == -1) {
syslog(LOG_ERR, "accept: %m");
exit(3);
}
dup2(acc, 0);
close(sock);
sock = 0;
} else {
/*
* To verify authenticity, we need to know the address of the
* client.
*/
if (getpeername(0, (struct sockaddr *)&peername, &namelen) < 0) {
syslog(LOG_ERR, "getpeername: %m");
exit(1);
}
}
peeraddr.addrtype = peername.sin_family;
peeraddr.length = sizeof(peername.sin_addr);
peeraddr.contents = (krb5_octet *)&peername.sin_addr;
if (retval = krb5_recvauth(context, (krb5_pointer)&sock,
SAMPLE_VERSION, server, &peeraddr,
0, 0, 0, /* no fetchfrom, keyproc or arg */
0, /* default rc type */
0, /* no flags */
0, /* don't need seq number */
&client,
0, 0 /* don't care about ticket or
authenticator */
)) {
syslog(LOG_ERR, "recvauth failed--%s", error_message(retval));
exit(1);
}
if (retval = krb5_unparse_name(context, client, &cname)) {
syslog(LOG_ERR, "unparse failed: %s", error_message(retval));
cname = "<unparse error>";
}
sprintf(repbuf, "You are %s\n", cname);
if (!retval)
free(cname);
xmitlen = htons(strlen(repbuf));
recv_data.length = strlen(repbuf);
recv_data.data = repbuf;
if ((retval = krb5_net_write(context, 0, (char *)&xmitlen,
sizeof(xmitlen))) < 0) {
syslog(LOG_ERR, "%m: while writing len to client");
exit(1);
}
if ((retval = krb5_net_write(context, 0, (char *)recv_data.data,
recv_data.length)) < 0) {
syslog(LOG_ERR, "%m: while writing data to client");
exit(1);
}
exit(0);
}
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