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/*
* lib/krb5/krb/mk_safe.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.
*
*
* krb5_mk_safe()
*/
#include <k5-int.h>
#include "cleanup.h"
#include "auth_con.h"
/*
Formats a KRB_SAFE message into outbuf.
userdata is formatted as the user data in the message.
sumtype specifies the encryption type; key specifies the key which
might be used to seed the checksum; sender_addr and recv_addr specify
the full addresses (host and port) of the sender and receiver.
The host portion of sender_addr is used to form the addresses used in the
KRB_SAFE message.
The outbuf buffer storage is allocated, and should be freed by the
caller when finished.
returns system errors
*/
static krb5_error_code
krb5_mk_safe_basic(context, userdata, keyblock, replaydata, local_addr,
remote_addr, sumtype, outbuf)
krb5_context context;
const krb5_data * userdata;
const krb5_keyblock * keyblock;
krb5_replay_data * replaydata;
const krb5_address * local_addr;
const krb5_address * remote_addr;
const krb5_cksumtype sumtype;
krb5_data * outbuf;
{
krb5_error_code retval;
krb5_safe safemsg;
krb5_octet zero_octet = 0;
krb5_checksum safe_checksum;
krb5_data *scratch1, *scratch2;
if (!valid_cksumtype(sumtype))
return KRB5_PROG_SUMTYPE_NOSUPP;
if (!is_coll_proof_cksum(sumtype) || !is_keyed_cksum(sumtype))
return KRB5KRB_AP_ERR_INAPP_CKSUM;
safemsg.user_data = *userdata;
safemsg.s_address = (krb5_address *) local_addr;
safemsg.r_address = (krb5_address *) remote_addr;
/* We should check too make sure one exists. */
safemsg.timestamp = replaydata->timestamp;
safemsg.usec = replaydata->usec;
safemsg.seq_number = replaydata->seq;
/*
* To do the checksum stuff, we need to encode the message with a
* zero-length zero-type checksum, then checksum the encoding, then
* re-encode with the checksum.
*/
safe_checksum.length = 0;
safe_checksum.checksum_type = 0;
safe_checksum.contents = &zero_octet;
safemsg.checksum = &safe_checksum;
if ((retval = encode_krb5_safe(&safemsg, &scratch1)))
return retval;
safe_checksum.length = krb5_checksum_size(context, sumtype);
if (!(safe_checksum.contents = (krb5_octet *) malloc(safe_checksum.length))) {
retval = ENOMEM;
goto cleanup_scratch;
}
if ((retval = krb5_calculate_checksum(context, sumtype, scratch1->data,
scratch1->length,
(krb5_pointer) keyblock->contents,
keyblock->length, &safe_checksum))) {
goto cleanup_checksum;
}
safemsg.checksum = &safe_checksum;
if ((retval = encode_krb5_safe(&safemsg, &scratch2))) {
goto cleanup_checksum;
}
*outbuf = *scratch2;
krb5_xfree(scratch2);
retval = 0;
cleanup_checksum:
krb5_xfree(safe_checksum.contents);
cleanup_scratch:
memset((char *)scratch1->data, 0, scratch1->length);
krb5_free_data(context, scratch1);
return retval;
}
KRB5_DLLIMP krb5_error_code KRB5_CALLCONV
krb5_mk_safe(context, auth_context, userdata, outbuf, outdata)
krb5_context context;
krb5_auth_context auth_context;
const krb5_data FAR * userdata;
krb5_data FAR * outbuf;
krb5_replay_data FAR * outdata;
{
krb5_error_code retval;
krb5_keyblock * keyblock;
krb5_replay_data replaydata;
/* Clear replaydata block */
memset((char *) &replaydata, 0, sizeof(krb5_replay_data));
/* Get keyblock */
if ((keyblock = auth_context->local_subkey) == NULL)
if ((keyblock = auth_context->remote_subkey) == NULL)
keyblock = auth_context->keyblock;
/* Get replay info */
if ((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_TIME) &&
(auth_context->rcache == NULL))
return KRB5_RC_REQUIRED;
if (((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_TIME) ||
(auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE)) &&
(outdata == NULL))
/* Need a better error */
return KRB5_RC_REQUIRED;
if ((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_TIME) ||
(auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_TIME)) {
if ((retval = krb5_us_timeofday(context, &replaydata.timestamp,
&replaydata.usec)))
return retval;
if (auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_TIME) {
outdata->timestamp = replaydata.timestamp;
outdata->usec = replaydata.usec;
}
}
if ((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) ||
(auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE)) {
replaydata.seq = auth_context->local_seq_number++;
if (auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE) {
outdata->seq = replaydata.seq;
}
}
{
krb5_address * premote_fulladdr = NULL;
krb5_address * plocal_fulladdr = NULL;
krb5_address remote_fulladdr;
krb5_address local_fulladdr;
CLEANUP_INIT(2);
if (auth_context->local_addr) {
if (auth_context->local_port) {
if (!(retval = krb5_make_fulladdr(context, auth_context->local_addr,
auth_context->local_port,
&local_fulladdr))){
CLEANUP_PUSH(local_fulladdr.contents, free);
plocal_fulladdr = &local_fulladdr;
} else {
goto error;
}
} else {
plocal_fulladdr = auth_context->local_addr;
}
}
if (auth_context->remote_addr) {
if (auth_context->remote_port) {
if (!(retval = krb5_make_fulladdr(context,auth_context->remote_addr,
auth_context->remote_port,
&remote_fulladdr))){
CLEANUP_PUSH(remote_fulladdr.contents, free);
premote_fulladdr = &remote_fulladdr;
} else {
CLEANUP_DONE();
goto error;
}
} else {
premote_fulladdr = auth_context->remote_addr;
}
}
if ((retval = krb5_mk_safe_basic(context, userdata, keyblock, &replaydata,
plocal_fulladdr, premote_fulladdr,
auth_context->safe_cksumtype, outbuf))) {
CLEANUP_DONE();
goto error;
}
CLEANUP_DONE();
}
if (auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_TIME) {
krb5_donot_replay replay;
if ((retval = krb5_gen_replay_name(context, auth_context->local_addr,
"_safe", &replay.client))) {
krb5_xfree(outbuf);
goto error;
}
replay.server = ""; /* XXX */
replay.cusec = replaydata.usec;
replay.ctime = replaydata.timestamp;
if ((retval = krb5_rc_store(context, auth_context->rcache, &replay))) {
/* should we really error out here? XXX */
krb5_xfree(outbuf);
goto error;
}
krb5_xfree(replay.client);
}
return 0;
error:
if ((auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) ||
(auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_RET_SEQUENCE))
auth_context->local_seq_number--;
return retval;
}
|
