Language/OS - Multiplatform Resource Library/LANGUAGE OS.iso/oper_sys/kerberos/pc/krb_src.lha/KSAMPLE/SAM_CLNT.C

C/C++ Source or Header | 1991-08-01 | 4.9 KB | 199 lines

/*
 * $Source: /mit/kerberos/src/appl/sample/RCS/sample_client.c,v $
 * $Author: jtkohl $
 *
 * Copyright 1987, 1988 by the Massachusetts Institute of Technology.
 *
 * For copying and distribution information,
 * please see the file <mit-copyright.h>.
 *
 * sample_client:
 * A sample Kerberos client, which connects to a server on a remote host,
 * at port "sample" (be sure to define it in /etc/services)
 * and authenticates itself to the server. The server then writes back
 * (in ASCII) the authenticated name.
 *
 * Usage:
 * sample_client <hostname> <checksum>
 *
 * <hostname> is the name of the foreign host to contact.
 *
 * <checksum> is an integer checksum to be used for the call to krb_mk_req()
 *    and mutual authentication
 *
 * If DEBUG is defined, authenticate to server "test.test".
 */

#ifndef    lint
static char rcsid_sample_client_c[] =
"$Header: sample_client.c,v 4.2 89/04/21 13:27:45 jtkohl Exp $";
#endif    lint

#include <mit_copy.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <krb.h>

#define SAMPLE_SERVICE    "sample"

#ifdef DEBUG
#define    TEST_SERVICE    "test"
#endif

#ifdef __BORLANDC__
int _stklen=16000;
#endif

extern int krb_debug,krb_ap_req_debug,des_debug;

static void close_sockets();
static int sock;

main(argc, argv)
int argc;
char **argv;
{
    struct servent *sp;
    struct hostent *hp;
    struct sockaddr_in sin, lsin;
    char *remote_host;
    int status;
    int namelen;
    KTEXT_ST ticket;
    char buf[512];
    long authopts;
    MSG_DAT msg_data;
    CREDENTIALS cred;
    Key_schedule sched;
    long cksum;
    long host_ip;

    krb_debug=1;
    krb_ap_req_debug=1;
    des_debug=3;
    if (argc != 3) {
    fprintf(stderr, "usage: %s <hostname> <checksum>\n",argv[0]);
    exit(1);
    }

    /* convert cksum to internal rep */
    cksum = (long) atoi(argv[2]);

    /* clear out the structure first */
    (void) bzero((char *)&sin, sizeof(sin));

    /* find the port number for knetd */
    sp = getservbyname(SAMPLE_SERVICE, "tcp");
    if (!sp) {
    fprintf(stderr,
        "unknown service %s/tcp; check /etc/services\n",
        SAMPLE_SERVICE);
    exit(1);
    }
    /* copy the port number */
    sin.sin_port = sp->s_port;
    sin.sin_family = AF_INET;
#if 1
    /* look up the server host */
    hp = gethostbyname(argv[1]);
    if (!hp) {
    fprintf(stderr, "unknown host %s\n",argv[1]);
    exit(1);
    }

    /* copy the hostname into non-volatile storage */
    remote_host = malloc(strlen(hp->h_name) + 1);
    (void) strcpy(remote_host, hp->h_name);

    /* set up the address of the foreign socket for connect() */
    sin.sin_family = hp->h_addrtype;
    (void) bcopy((char *)hp->h_addr,
         (char *)&sin.sin_addr,
         hp->h_length);
#else    /* DNS version */
    printf("Before rhost\n");
    /* copy the hostname into non-volatile storage */
    remote_host = malloc(strlen(argv[1]) + 1);
    (void) strcpy(remote_host, argv[1]);
    host_ip=rhost(&argv[1]);
    sin.sin_family=AF_INET;
    sin.sin_addr.s_addr=host_ip;
#endif
    /* open a TCP socket */
    sock = socket(PF_INET, SOCK_STREAM, 0);
    if (sock < 0) {
        soperror("socket");
    exit(1);
    }
    atexit(close_sockets);

    /* connect to the server */
    if (connect(sock,(struct sockaddr*) &sin, sizeof(sin)) < 0) {
        soperror("connect");
    exit(1);
    }

    /* find out who I am, now that we are connected and therefore bound */
    namelen = sizeof(lsin);
    if (getsockname(sock, (struct sockaddr *) &lsin, &namelen) < 0) {
        soperror("getsockname");
    exit(1);
    }

    /* call Kerberos library routine to obtain an authenticator,
       pass it over the socket to the server, and obtain mutual
       authentication. */

    authopts = KOPT_DO_MUTUAL;
    status = krb_sendauth(authopts, sock, &ticket,
#ifdef DEBUG
              TEST_SERVICE, TEST_SERVICE,
#else
              SAMPLE_SERVICE, remote_host,
#endif
              NULL, cksum, &msg_data, &cred,
              sched, &lsin, &sin, "VERSION9");
    if (status != KSUCCESS) {
    fprintf(stderr, "%s: cannot authenticate to server: %s\n",
        argv[0], krb_err_txt[status]);
    exit(1);
    }

    /* After we send the authenticator to the server, it will write
       back the name we authenticated to. Read what it has to say. */
    status = soread(sock, buf, 512);
    if (status < 0) {
    perror("read");
    exit(1);
    }

    /* make sure it's null terminated before printing */
    if (status < 512)
    buf[status] = '\0';
    printf("The server says:\n%s\n", buf);

    exit(0);
}

static void close_sockets()
{
    printf("\nClosing socket %d\n",sock);
    soclose(sock);
}

void dump(char *hdr,char far*p,int len)
{
    FILE *fp;
    int i;

    fp=fopen("dump","a");
    fprintf(fp,"%s\n",hdr);
    for(i=0;i<len;i++,p++)
        fprintf(fp,"%3d%c%c",*p,isgraph(*p) ? *p : ' ',
            i%40 ? ' ' : '\n');
    fprintf(fp,"\n");
}