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/*
* $Source$
* $Author$
*
* Copyright 1990 by the Massachusetts Institute of Technology.
*
* For copying and distribution information, please see the file
* <krb5/copyright.h>.
*
* Sample Kerberos v5 client.
*
* Usage: sample_client hostname
*/
#if !defined(lint) && !defined(SABER)
static char rcsid_sclient_c [] =
"$Id$";
#endif /* !lint & !SABER */
#include <krb5/copyright.h>
#include <krb5/krb5.h>
#include <krb5/ext-proto.h>
#include <krb5/libos-proto.h>
#include <stdio.h>
#include <ctype.h>
#include <com_err.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <signal.h>
#include "sample.h"
void
main(argc, argv)
int argc;
char *argv[];
{
struct servent *sp;
struct hostent *hp;
struct sockaddr_in sin, lsin;
char *remote_host;
register char *cp;
int sock, namelen;
krb5_data send_data;
krb5_checksum send_cksum;
krb5_error_code retval;
krb5_ccache ccdef;
krb5_principal server;
char **hrealms;
short xmitlen;
char sbuf[512];
if (argc != 2) {
fprintf(stderr, "usage: %s <hostname>\n",argv[0]);
exit(1);
}
krb5_init_ets();
(void) signal(SIGPIPE, SIG_IGN);
if (!valid_cksumtype(CKSUMTYPE_CRC32)) {
com_err(argv[0], KRB5_PROG_SUMTYPE_NOSUPP, "while using CRC-32");
exit(1);
}
/* clear out the structure first */
(void) memset((char *)&sin, 0, 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;
/* look up the server host */
hp = gethostbyname(argv[1]);
if (!hp) {
fprintf(stderr, "unknown host %s\n",argv[1]);
exit(1);
}
if (retval = krb5_get_host_realm(hp->h_name, &hrealms)) {
com_err(argv[0], retval, "while determining realm(s) of %s",
hp->h_name);
exit(1);
}
if (strlen(hp->h_name)+strlen(SAMPLE_SERVICE)+strlen(hrealms[0])+3 >
sizeof(sbuf)) {
fprintf(stderr, "hostname too long!\n");
exit(1);
}
/* copy the hostname into non-volatile storage */
remote_host = malloc(strlen(hp->h_name) + 1);
(void) strcpy(remote_host, hp->h_name);
/* lower-case to get name for "instance" part of service name */
for (cp = remote_host; *cp; cp++)
if (isupper(*cp))
*cp = tolower(*cp);
memset(sbuf, 0, sizeof(sbuf));
strcpy(sbuf, SAMPLE_SERVICE);
strcat(sbuf, "/");
strcat(sbuf, remote_host);
strcat(sbuf, "@");
strcat(sbuf, hrealms[0]);
(void) krb5_free_host_realm(hrealms);
if (retval = krb5_parse_name(sbuf, &server)) {
com_err(argv[0], retval, "while parsing service name %s", sbuf);
exit(1);
}
/* set up the address of the foreign socket for connect() */
sin.sin_family = hp->h_addrtype;
(void) memcpy((char *)&sin.sin_addr,
(char *)hp->h_addr,
sizeof(hp->h_addr));
/* open a TCP socket */
sock = socket(PF_INET, SOCK_STREAM, 0);
if (sock < 0) {
perror("socket");
exit(1);
}
/* connect to the server */
if (connect(sock, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
perror("connect");
close(sock);
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) {
perror("getsockname");
close(sock);
exit(1);
}
/* compute checksum, using CRC-32 */
if (!(send_cksum.contents = (krb5_octet *)
malloc(krb5_cksumarray[CKSUMTYPE_CRC32]->checksum_length))) {
com_err(argv[0], ENOMEM, "while allocating checksum");
exit(1);
}
/* choose some random stuff to compute checksum from */
if (retval = (*krb5_cksumarray[CKSUMTYPE_CRC32]->
sum_func)(remote_host,
strlen(remote_host),
0,
0, /* if length is 0, crc-32 doesn't
use the seed */
&send_cksum)) {
com_err(argv[0], retval, "while computing checksum");
exit(1);
}
if (retval = krb5_cc_default(&ccdef)) {
com_err(argv[0], retval, "while getting default ccache");
exit(1);
}
if (retval = krb5_mk_req(server, 0, &send_cksum, ccdef, &send_data)) {
com_err(argv[0], retval, "while preparing AP_REQ");
exit(1);
}
xmitlen = htons(send_data.length);
if ((retval = krb5_net_write(sock, (char *)&xmitlen,
sizeof(xmitlen))) < 0) {
com_err(argv[0], errno, "while writing len to server");
exit(1);
}
if ((retval = krb5_net_write(sock, (char *)send_data.data,
send_data.length)) < 0) {
com_err(argv[0], errno, "while writing data to server");
exit(1);
}
xfree(send_data.data);
if ((retval = krb5_net_read(sock, (char *)&xmitlen,
sizeof(xmitlen))) <= 0) {
if (retval == 0)
errno = ECONNRESET; /* XXX */
com_err(argv[0], errno, "while reading data from server");
exit(1);
}
send_data.length = ntohs(xmitlen);
if (!(send_data.data = (char *)malloc(send_data.length + 1))) {
com_err(argv[0], ENOMEM, "while allocating buffer to read from server");
exit(1);
}
if ((retval = krb5_net_read(sock, (char *)send_data.data,
send_data.length)) <= 0) {
if (retval == 0)
errno = ECONNRESET; /* XXX */
com_err(argv[0], errno, "while reading data from server");
exit(1);
}
send_data.data[send_data.length] = '\0';
printf("reply len %d, contents:\n%s\n",send_data.length,send_data.data);
exit(0);
}
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