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/*
* lib/krb5/krb/compat_recv.c
*
* Copyright 1993 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.
*
*
* convenience sendauth/recvauth functions, with compatibility with V4
* recvauth.
*
* NOTE: linking in this function will pull in V4 kerberos routines.
*
* WARNING: In the V4-style arguments, the ticket and kdata arguments
* have different types than the V4 recvauth; in V4, they were KTEXT
* and AUTH_DAT *, respectively. Here, they are KTEXT * and AUTH_DAT **
* and they are allocated by recvauth if and only if we end up talking
* to a V4 sendauth.
*/
#define NEED_SOCKETS
#include "k5-int.h"
#ifndef _MSDOS
#include <kerberosIV/krb.h>
#include <kerberosIV/krb4-proto.h>
#include "com_err.h"
#include <errno.h>
#include <stdio.h>
#include <string.h>
static int krb_v4_recvauth();
#define KRB_V4_SENDAUTH_VERS "AUTHV0.1" /* MUST be 8 chars long */
#define KRB_V5_SENDAUTH_VERS "KRB5_SENDAUTH_V1.0"
#define KRB5_RECVAUTH_V4 4
#define KRB5_RECVAUTH_V5 5
krb5_error_code
krb5_compat_recvauth(context, auth_context,
/* IN */
fdp, appl_version, server, flags, keytab,
v4_options, v4_service, v4_instance, v4_faddr, v4_laddr,
v4_filename,
/* OUT */
ticket,
auth_sys, v4_kdata, v4_schedule, v4_version)
krb5_context context;
krb5_auth_context **auth_context;
krb5_pointer fdp;
char *appl_version;
krb5_principal server;
krb5_int32 flags;
krb5_keytab keytab;
krb5_ticket ** ticket;
krb5_int32 *auth_sys;
/*
* Version 4 arguments
*/
krb5_int32 v4_options; /* bit-pattern of options */
char *v4_service; /* service expected */
char *v4_instance; /* inst expected (may be filled in) */
struct sockaddr_in *v4_faddr; /* foreign address */
struct sockaddr_in *v4_laddr; /* local address */
AUTH_DAT **v4_kdata; /* kerberos data (returned) */
char *v4_filename; /* name of file with service keys */
Key_schedule v4_schedule; /* key schedule (return) */
char *v4_version; /* version string (filled in) */
{
union verslen {
krb5_int32 len;
char vers[4];
} vers;
char *buf;
int len, length;
krb5_int32 retval;
int fd = *( (int *) fdp);
#ifdef KRB5_KRB4_COMPAT
KTEXT v4_ticket; /* storage for client's ticket */
#endif
if ((retval = krb5_net_read(context, fd, vers.vers, 4)) != 4)
return((retval < 0) ? errno : ECONNABORTED);
#ifdef KRB5_KRB4_COMPAT
if (!strncmp(vers.vers, KRB_V4_SENDAUTH_VERS, 4)) {
/*
* We must be talking to a V4 sendauth; read in the
* rest of the version string and make sure.
*/
if ((retval = krb5_net_read(context, fd, vers.vers, 4)) != 4)
return((retval < 0) ? errno : ECONNABORTED);
if (strncmp(vers.vers, KRB_V4_SENDAUTH_VERS+4, 4))
return KRB5_SENDAUTH_BADAUTHVERS;
*auth_sys = KRB5_RECVAUTH_V4;
*v4_kdata = (AUTH_DAT *) malloc( sizeof(AUTH_DAT) );
v4_ticket = (KTEXT) malloc(sizeof(KTEXT_ST));
retval = krb_v4_recvauth(v4_options, fd, v4_ticket,
v4_service, v4_instance, v4_faddr,
v4_laddr, *v4_kdata, v4_filename,
v4_schedule, v4_version);
krb5_xfree(v4_ticket);
/*
* XXX error code translation?
*/
switch (retval) {
case RD_AP_OK:
return 0;
case RD_AP_TIME:
return KRB5KRB_AP_ERR_SKEW;
case RD_AP_EXP:
return KRB5KRB_AP_ERR_TKT_EXPIRED;
case RD_AP_NYV:
return KRB5KRB_AP_ERR_TKT_NYV;
case RD_AP_NOT_US:
return KRB5KRB_AP_ERR_NOT_US;
case RD_AP_UNDEC:
return KRB5KRB_AP_ERR_BAD_INTEGRITY;
case RD_AP_REPEAT:
return KRB5KRB_AP_ERR_REPEAT;
case RD_AP_MSG_TYPE:
return KRB5KRB_AP_ERR_MSG_TYPE;
case RD_AP_MODIFIED:
return KRB5KRB_AP_ERR_MODIFIED;
case RD_AP_ORDER:
return KRB5KRB_AP_ERR_BADORDER;
case RD_AP_BADD:
return KRB5KRB_AP_ERR_BADADDR;
default:
return KRB5_SENDAUTH_BADRESPONSE;
}
}
#endif
/*
* Assume that we're talking to a V5 recvauth; read in the
* the version string, and make sure it matches.
*/
len = (int) ntohl(vers.len);
if (len < 0 || len > 255)
return KRB5_SENDAUTH_BADAUTHVERS;
buf = malloc(len);
if (!buf)
return ENOMEM;
length = krb5_net_read(context, fd, buf, len);
if (len != length) {
krb5_xfree(buf);
if (len < 0)
return errno;
else
return ECONNABORTED;
}
if (strcmp(buf, KRB_V5_SENDAUTH_VERS)) {
krb5_xfree(buf);
return KRB5_SENDAUTH_BADAUTHVERS;
}
krb5_xfree(buf);
*auth_sys = KRB5_RECVAUTH_V5;
retval = krb5_recvauth(context, auth_context, fdp, appl_version, server,
flags | KRB5_RECVAUTH_SKIP_VERSION,
keytab, ticket);
return retval;
}
#ifndef max
#define max(a,b) (((a) > (b)) ? (a) : (b))
#endif /* max */
#ifdef KRB5_KRB4_COMPAT
static int
krb_v4_recvauth(options, fd, ticket, service, instance, faddr, laddr, kdata,
filename, schedule, version)
long options; /* bit-pattern of options */
int fd; /* file descr. to read from */
KTEXT ticket; /* storage for client's ticket */
char *service; /* service expected */
char *instance; /* inst expected (may be filled in) */
struct sockaddr_in *faddr; /* address of foreign host on fd */
struct sockaddr_in *laddr; /* local address */
AUTH_DAT *kdata; /* kerberos data (returned) */
char *filename; /* name of file with service keys */
Key_schedule schedule; /* key schedule (return) */
char *version; /* version string (filled in) */
{
int cc, old_vers = 0;
int rem;
krb5_int32 tkt_len, priv_len;
krb5_ui_4 cksum;
u_char tmp_buf[MAX_KTXT_LEN+max(KRB_SENDAUTH_VLEN+1,21)];
/* read the application version string */
if ((krb_net_read(fd, version, KRB_SENDAUTH_VLEN) !=
KRB_SENDAUTH_VLEN))
return(errno);
version[KRB_SENDAUTH_VLEN] = '\0';
/* get the length of the ticket */
if (krb_net_read(fd, (char *)&tkt_len, sizeof(tkt_len)) !=
sizeof(tkt_len))
return(errno);
/* sanity check */
ticket->length = ntohl((unsigned long)tkt_len);
if ((ticket->length <= 0) || (ticket->length > MAX_KTXT_LEN)) {
if (options & KOPT_DO_MUTUAL) {
rem = KFAILURE;
goto mutual_fail;
} else
return(KFAILURE); /* XXX there may still be junk on the fd? */
}
/* read the ticket */
if (krb_net_read(fd, (char *) ticket->dat, ticket->length)
!= ticket->length)
return(errno);
/*
* now have the ticket. decrypt it to get the authenticated
* data.
*/
rem = krb_rd_req(ticket,service,instance,faddr->sin_addr.s_addr,
kdata,filename);
if (old_vers) return(rem); /* XXX can't do mutual with old client */
/* if we are doing mutual auth, compose a response */
if (options & KOPT_DO_MUTUAL) {
if (rem != KSUCCESS)
/* the krb_rd_req failed */
goto mutual_fail;
/* add one to the (formerly) sealed checksum, and re-seal it
for return to the client */
cksum = kdata->checksum + 1;
cksum = htonl(cksum);
#ifndef NOENCRYPTION
key_sched(kdata->session,schedule);
#endif /* !NOENCRYPTION */
priv_len = krb_mk_priv((unsigned char *)&cksum,
tmp_buf,
(unsigned long) sizeof(cksum),
schedule,
kdata->session,
laddr,
faddr);
if (priv_len < 0) {
/* re-sealing failed; notify the client */
rem = KFAILURE; /* XXX */
mutual_fail:
priv_len = -1;
tkt_len = htonl((unsigned long) priv_len);
/* a length of -1 is interpreted as an authentication
failure by the client */
if ((cc = krb_net_write(fd, (char *)&tkt_len, sizeof(tkt_len)))
!= sizeof(tkt_len))
return(cc);
return(rem);
} else {
/* re-sealing succeeded, send the private message */
tkt_len = htonl((unsigned long)priv_len);
if ((cc = krb_net_write(fd, (char *)&tkt_len, sizeof(tkt_len)))
!= sizeof(tkt_len))
return(cc);
if ((cc = krb_net_write(fd, (char *)tmp_buf, (int) priv_len))
!= (int) priv_len)
return(cc);
}
}
return(rem);
}
#endif
#endif
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