KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_mk_rep(krb5_context context,
krb5_auth_context auth_context,
krb5_data *outbuf)
{
krb5_error_code ret;
AP_REP ap;
EncAPRepPart body;
u_char *buf = NULL;
size_t buf_size;
size_t len = 0;
krb5_crypto crypto;
ap.pvno = 5;
ap.msg_type = krb_ap_rep;
memset (&body, 0, sizeof(body));
body.ctime = auth_context->authenticator->ctime;
body.cusec = auth_context->authenticator->cusec;
if (auth_context->flags & KRB5_AUTH_CONTEXT_USE_SUBKEY) {
if (auth_context->local_subkey == NULL) {
ret = krb5_auth_con_generatelocalsubkey(context,
auth_context,
auth_context->keyblock);
if(ret) {
free_EncAPRepPart(&body);
return ret;
}
}
ret = krb5_copy_keyblock(context, auth_context->local_subkey,
&body.subkey);
if (ret) {
free_EncAPRepPart(&body);
return krb5_enomem(context);
}
} else
body.subkey = NULL;
if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
if(auth_context->local_seqnumber == 0)
krb5_generate_seq_number (context,
auth_context->keyblock,
&auth_context->local_seqnumber);
ALLOC(body.seq_number, 1);
if (body.seq_number == NULL) {
free_EncAPRepPart(&body);
return krb5_enomem(context);
}
*(body.seq_number) = auth_context->local_seqnumber;
} else
body.seq_number = NULL;
ap.enc_part.etype = auth_context->keyblock->keytype;
ap.enc_part.kvno = NULL;
ASN1_MALLOC_ENCODE(EncAPRepPart, buf, buf_size, &body, &len, ret);
free_EncAPRepPart (&body);
if(ret)
return ret;
if (buf_size != len)
krb5_abortx(context, "internal error in ASN.1 encoder");
ret = krb5_crypto_init(context, auth_context->keyblock,
0 /* ap.enc_part.etype */, &crypto);
if (ret) {
free (buf);
return ret;
}
ret = krb5_encrypt (context,
crypto,
KRB5_KU_AP_REQ_ENC_PART,
buf + buf_size - len,
len,
&ap.enc_part.cipher);
krb5_crypto_destroy(context, crypto);
free(buf);
if (ret)
return ret;
ASN1_MALLOC_ENCODE(AP_REP, outbuf->data, outbuf->length, &ap, &len, ret);
if (ret == 0 && outbuf->length != len)
krb5_abortx(context, "internal error in ASN.1 encoder");
free_AP_REP (&ap);
return ret;
}
krb5_error_code KRB5_CALLCONV
krb5_mk_req_extended(krb5_context context, krb5_auth_context *auth_context,
krb5_flags ap_req_options, krb5_data *in_data,
krb5_creds *in_creds, krb5_data *outbuf)
{
krb5_error_code retval;
krb5_checksum checksum;
krb5_checksum *checksump = 0;
krb5_auth_context new_auth_context;
krb5_enctype *desired_etypes = NULL;
krb5_ap_req request;
krb5_data *scratch = 0;
krb5_data *toutbuf;
request.ap_options = ap_req_options & AP_OPTS_WIRE_MASK;
request.authenticator.ciphertext.data = NULL;
request.ticket = 0;
if (!in_creds->ticket.length)
return(KRB5_NO_TKT_SUPPLIED);
if ((ap_req_options & AP_OPTS_ETYPE_NEGOTIATION) &&
!(ap_req_options & AP_OPTS_MUTUAL_REQUIRED))
return(EINVAL);
/* we need a native ticket */
if ((retval = decode_krb5_ticket(&(in_creds)->ticket, &request.ticket)))
return(retval);
/* verify that the ticket is not expired */
if ((retval = krb5int_validate_times(context, &in_creds->times)) != 0)
goto cleanup;
/* generate auth_context if needed */
if (*auth_context == NULL) {
if ((retval = krb5_auth_con_init(context, &new_auth_context)))
goto cleanup;
*auth_context = new_auth_context;
}
if ((*auth_context)->key != NULL) {
krb5_k_free_key(context, (*auth_context)->key);
(*auth_context)->key = NULL;
}
/* set auth context keyblock */
if ((retval = krb5_k_create_key(context, &in_creds->keyblock,
&((*auth_context)->key))))
goto cleanup;
/* generate seq number if needed */
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 == 0)) {
if ((retval = krb5_generate_seq_number(context, &in_creds->keyblock,
&(*auth_context)->local_seq_number)))
goto cleanup;
}
/* generate subkey if needed */
if ((ap_req_options & AP_OPTS_USE_SUBKEY)&&(!(*auth_context)->send_subkey)) {
retval = k5_generate_and_save_subkey(context, *auth_context,
&in_creds->keyblock,
in_creds->keyblock.enctype);
if (retval)
goto cleanup;
}
if (!in_data && (*auth_context)->checksum_func) {
retval = (*auth_context)->checksum_func( context,
*auth_context,
(*auth_context)->checksum_func_data,
&in_data);
if (retval)
goto cleanup;
}
if (in_data) {
if ((*auth_context)->req_cksumtype == 0x8003) {
/* XXX Special hack for GSSAPI */
checksum.checksum_type = 0x8003;
checksum.length = in_data->length;
checksum.contents = (krb5_octet *) in_data->data;
} else {
krb5_enctype enctype = krb5_k_key_enctype(context,
(*auth_context)->key);
krb5_cksumtype cksumtype = ap_req_cksum(context, *auth_context,
enctype);
if ((retval = krb5_k_make_checksum(context,
cksumtype,
(*auth_context)->key,
KRB5_KEYUSAGE_AP_REQ_AUTH_CKSUM,
in_data, &checksum)))
goto cleanup_cksum;
}
checksump = &checksum;
}
/* Generate authenticator */
if (((*auth_context)->authentp = (krb5_authenticator *)malloc(sizeof(
krb5_authenticator))) == NULL) {
retval = ENOMEM;
goto cleanup_cksum;
}
if (ap_req_options & AP_OPTS_ETYPE_NEGOTIATION) {
if ((*auth_context)->permitted_etypes == NULL) {
retval = krb5_get_tgs_ktypes(context, in_creds->server, &desired_etypes);
if (retval)
goto cleanup_cksum;
} else
desired_etypes = (*auth_context)->permitted_etypes;
}
TRACE_MK_REQ(context, in_creds, (*auth_context)->local_seq_number,
(*auth_context)->send_subkey, &in_creds->keyblock);
if ((retval = generate_authenticator(context,
(*auth_context)->authentp,
in_creds->client, checksump,
(*auth_context)->send_subkey,
(*auth_context)->local_seq_number,
in_creds->authdata,
(*auth_context)->ad_context,
desired_etypes,
in_creds->keyblock.enctype)))
goto cleanup_cksum;
/* encode the authenticator */
if ((retval = encode_krb5_authenticator((*auth_context)->authentp,
&scratch)))
goto cleanup_cksum;
/* call the encryption routine */
if ((retval = krb5_encrypt_helper(context, &in_creds->keyblock,
KRB5_KEYUSAGE_AP_REQ_AUTH,
scratch, &request.authenticator)))
goto cleanup_cksum;
if ((retval = encode_krb5_ap_req(&request, &toutbuf)))
goto cleanup_cksum;
*outbuf = *toutbuf;
free(toutbuf);
cleanup_cksum:
/* Null out these fields, to prevent pointer sharing problems;
* they were supplied by the caller
*/
if ((*auth_context)->authentp != NULL) {
(*auth_context)->authentp->client = NULL;
(*auth_context)->authentp->checksum = NULL;
}
if (checksump && checksump->checksum_type != 0x8003)
free(checksump->contents);
cleanup:
if (desired_etypes &&
desired_etypes != (*auth_context)->permitted_etypes)
free(desired_etypes);
if (request.ticket)
krb5_free_ticket(context, request.ticket);
if (request.authenticator.ciphertext.data) {
(void) memset(request.authenticator.ciphertext.data, 0,
request.authenticator.ciphertext.length);
free(request.authenticator.ciphertext.data);
}
if (scratch) {
memset(scratch->data, 0, scratch->length);
free(scratch->data);
free(scratch);
}
return retval;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
_krb5_build_authenticator (krb5_context context,
krb5_auth_context auth_context,
krb5_enctype enctype,
krb5_creds *cred,
Checksum *cksum,
krb5_data *result,
krb5_key_usage usage)
{
Authenticator auth;
u_char *buf = NULL;
size_t buf_size;
size_t len = 0;
krb5_error_code ret;
krb5_crypto crypto;
memset(&auth, 0, sizeof(auth));
auth.authenticator_vno = 5;
copy_Realm(&cred->client->realm, &auth.crealm);
copy_PrincipalName(&cred->client->name, &auth.cname);
krb5_us_timeofday (context, &auth.ctime, &auth.cusec);
ret = krb5_auth_con_getlocalsubkey(context, auth_context, &auth.subkey);
if(ret)
goto fail;
if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_SEQUENCE) {
if(auth_context->local_seqnumber == 0)
krb5_generate_seq_number (context,
&cred->session,
&auth_context->local_seqnumber);
ALLOC(auth.seq_number, 1);
if(auth.seq_number == NULL) {
ret = ENOMEM;
goto fail;
}
*auth.seq_number = auth_context->local_seqnumber;
} else
auth.seq_number = NULL;
auth.authorization_data = NULL;
if (cksum) {
ALLOC(auth.cksum, 1);
if (auth.cksum == NULL) {
ret = ENOMEM;
goto fail;
}
ret = copy_Checksum(cksum, auth.cksum);
if (ret)
goto fail;
if (auth.cksum->cksumtype == CKSUMTYPE_GSSAPI) {
/*
* This is not GSS-API specific, we only enable it for
* GSS for now
*/
ret = make_etypelist(context, &auth.authorization_data);
if (ret)
goto fail;
}
}
/* XXX - Copy more to auth_context? */
auth_context->authenticator->ctime = auth.ctime;
auth_context->authenticator->cusec = auth.cusec;
ASN1_MALLOC_ENCODE(Authenticator, buf, buf_size, &auth, &len, ret);
if (ret)
goto fail;
if(buf_size != len)
krb5_abortx(context, "internal error in ASN.1 encoder");
ret = krb5_crypto_init(context, &cred->session, enctype, &crypto);
if (ret)
goto fail;
ret = krb5_encrypt (context,
crypto,
usage /* KRB5_KU_AP_REQ_AUTH */,
buf,
len,
result);
krb5_crypto_destroy(context, crypto);
if (ret)
goto fail;
fail:
free_Authenticator (&auth);
free (buf);
return ret;
}
static krb5_error_code
k5_mk_rep(krb5_context context, krb5_auth_context auth_context,
krb5_data *outbuf, int dce_style)
{
krb5_error_code retval;
krb5_ap_rep_enc_part repl;
krb5_ap_rep reply;
krb5_data * scratch;
krb5_data * toutbuf;
/* Make the reply */
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 == 0)) {
if ((retval = krb5_generate_seq_number(context,
&auth_context->key->keyblock,
&auth_context->local_seq_number)))
return(retval);
}
if (dce_style) {
krb5_us_timeofday(context, &repl.ctime, &repl.cusec);
} else {
repl.ctime = auth_context->authentp->ctime;
repl.cusec = auth_context->authentp->cusec;
}
if (dce_style)
repl.subkey = NULL;
else if (auth_context->auth_context_flags & KRB5_AUTH_CONTEXT_USE_SUBKEY) {
assert(auth_context->negotiated_etype != ENCTYPE_NULL);
retval = k5_generate_and_save_subkey(context, auth_context,
&auth_context->key->keyblock,
auth_context->negotiated_etype);
if (retval)
return retval;
repl.subkey = &auth_context->send_subkey->keyblock;
} else
repl.subkey = auth_context->authentp->subkey;
if (dce_style)
repl.seq_number = auth_context->remote_seq_number;
else
repl.seq_number = auth_context->local_seq_number;
TRACE_MK_REP(context, repl.ctime, repl.cusec, repl.subkey,
repl.seq_number);
/* encode it before encrypting */
if ((retval = encode_krb5_ap_rep_enc_part(&repl, &scratch)))
return retval;
if ((retval = k5_encrypt_keyhelper(context, auth_context->key,
KRB5_KEYUSAGE_AP_REP_ENCPART, scratch,
&reply.enc_part)))
goto cleanup_scratch;
if (!(retval = encode_krb5_ap_rep(&reply, &toutbuf))) {
*outbuf = *toutbuf;
free(toutbuf);
}
memset(reply.enc_part.ciphertext.data, 0, reply.enc_part.ciphertext.length);
free(reply.enc_part.ciphertext.data);
reply.enc_part.ciphertext.length = 0;
reply.enc_part.ciphertext.data = 0;
cleanup_scratch:
memset(scratch->data, 0, scratch->length);
krb5_free_data(context, scratch);
return retval;
}
