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/*
* lib/krb5/krb/recvauth.c
*
* Copyright 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.
*
*
* convenience sendauth/recvauth functions
*/
#define NEED_SOCKETS
#include "k5-int.h"
#include "auth_con.h"
#include "com_err.h"
#include <errno.h>
#include <stdio.h>
#include <string.h>
static char *sendauth_version = "KRB5_SENDAUTH_V1.0";
krb5_error_code
krb5_recvauth(context, auth_context,
/* IN */
fd, appl_version, server, flags, keytab,
/* OUT */
ticket)
krb5_context context;
krb5_auth_context * auth_context;
krb5_pointer fd;
char * appl_version;
krb5_principal server;
krb5_int32 flags;
krb5_keytab keytab;
krb5_ticket ** ticket;
{
krb5_auth_context new_auth_context;
krb5_flags ap_option;
krb5_error_code retval, problem;
krb5_data inbuf;
krb5_data outbuf;
krb5_rcache rcache = 0;
krb5_octet response;
krb5_data null_server;
/*
* Zero out problem variable. If problem is set at the end of
* the intial version negotiation section, it means that we
* need to send an error code back to the client application
* and exit.
*/
problem = 0;
if (!(flags & KRB5_RECVAUTH_SKIP_VERSION)) {
/*
* First read the sendauth version string and check it.
*/
if ((retval = krb5_read_message(context, fd, &inbuf)))
return(retval);
if (strcmp(inbuf.data, sendauth_version)) {
krb5_xfree(inbuf.data);
problem = KRB5_SENDAUTH_BADAUTHVERS;
}
krb5_xfree(inbuf.data);
}
if (flags & KRB5_RECVAUTH_BADAUTHVERS)
problem = KRB5_SENDAUTH_BADAUTHVERS;
/*
* Do the same thing for the application version string.
*/
if ((retval = krb5_read_message(context, fd, &inbuf)))
return(retval);
if (strcmp(inbuf.data, appl_version)) {
krb5_xfree(inbuf.data);
if (!problem)
problem = KRB5_SENDAUTH_BADAPPLVERS;
}
krb5_xfree(inbuf.data);
/*
* OK, now check the problem variable. If it's zero, we're
* fine and we can continue. Otherwise, we have to signal an
* error to the client side and bail out.
*/
switch (problem) {
case 0:
response = 0;
break;
case KRB5_SENDAUTH_BADAUTHVERS:
response = 1;
break;
case KRB5_SENDAUTH_BADAPPLVERS:
response = 2;
break;
default:
/*
* Should never happen!
*/
response = 255;
#ifdef SENDAUTH_DEBUG
fprintf(stderr, "Programming botch in recvauth! problem = %d",
problem);
abort();
#endif
break;
}
/*
* Now we actually write the response. If the response is non-zero,
* exit with a return value of problem
*/
if ((krb5_net_write(context, *((int *)fd), (char *)&response, 1)) < 0) {
return(problem); /* We'll return the top-level problem */
}
if (problem)
return(problem);
/* We are clear of errors here */
/*
* Now, let's read the AP_REQ message and decode it
*/
if ((retval = krb5_read_message(context, fd, &inbuf)))
return retval;
if (*auth_context == NULL) {
problem = krb5_auth_con_init(context, &new_auth_context);
*auth_context = new_auth_context;
}
if ((!problem) && ((*auth_context)->rcache == NULL)) {
/*
* Setup the replay cache.
*/
if (server) {
problem = krb5_get_server_rcache(context,
krb5_princ_component(context, server, 0), &rcache);
} else {
null_server.length = 7;
null_server.data = "default";
problem = krb5_get_server_rcache(context, &null_server, &rcache);
}
if (!problem)
problem = krb5_auth_con_setrcache(context, *auth_context, rcache);
}
if (!problem) {
problem = krb5_rd_req(context, auth_context, &inbuf, server,
keytab, &ap_option, ticket);
krb5_xfree(inbuf.data);
}
/*
* If there was a problem, send back a krb5_error message,
* preceeded by the length of the krb5_error message. If
* everything's ok, send back 0 for the length.
*/
if (problem) {
krb5_error error;
const char *message;
memset((char *)&error, 0, sizeof(error));
krb5_us_timeofday(context, &error.stime, &error.susec);
error.server = server;
error.error = problem - ERROR_TABLE_BASE_krb5;
if (error.error > 127)
error.error = KRB_ERR_GENERIC;
message = error_message(problem);
error.text.length = strlen(message) + 1;
if (!(error.text.data = malloc(error.text.length))) {
retval = ENOMEM;
goto cleanup;
}
strcpy(error.text.data, message);
if ((retval = krb5_mk_error(context, &error, &outbuf))) {
free(error.text.data);
goto cleanup;
}
free(error.text.data);
} else {
outbuf.length = 0;
outbuf.data = 0;
}
retval = krb5_write_message(context, fd, &outbuf);
if (outbuf.data) {
krb5_xfree(outbuf.data);
/* We sent back an error, we need cleanup then return */
retval = problem;
goto cleanup;
}
if (retval)
goto cleanup;
/* Here lies the mutual authentication stuff... */
if ((ap_option & AP_OPTS_MUTUAL_REQUIRED)) {
if ((retval = krb5_mk_rep(context, *auth_context, &outbuf))) {
return(retval);
}
retval = krb5_write_message(context, fd, &outbuf);
krb5_xfree(outbuf.data);
}
cleanup:;
if (retval) {
if (rcache)
krb5_rc_close(context, rcache);
krb5_auth_con_free(context, *auth_context);
}
return retval;
}
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