static krb5_error_code
get_cred_kdc(krb5_context context,
krb5_ccache id,
krb5_kdc_flags flags,
krb5_addresses *addresses,
krb5_creds *in_creds,
krb5_creds *krbtgt,
krb5_principal impersonate_principal,
Ticket *second_ticket,
krb5_creds *out_creds)
{
TGS_REQ req;
krb5_data enc;
krb5_data resp;
krb5_kdc_rep rep;
KRB_ERROR error;
krb5_error_code ret;
unsigned nonce;
krb5_keyblock *subkey = NULL;
size_t len;
Ticket second_ticket_data;
METHOD_DATA padata;
krb5_data_zero(&resp);
krb5_data_zero(&enc);
padata.val = NULL;
padata.len = 0;
krb5_generate_random_block(&nonce, sizeof(nonce));
nonce &= 0xffffffff;
if(flags.b.enc_tkt_in_skey && second_ticket == NULL){
ret = decode_Ticket(in_creds->second_ticket.data,
in_creds->second_ticket.length,
&second_ticket_data, &len);
if(ret)
return ret;
second_ticket = &second_ticket_data;
}
if (impersonate_principal) {
krb5_crypto crypto;
PA_S4U2Self self;
krb5_data data;
void *buf;
size_t size;
self.name = impersonate_principal->name;
self.realm = impersonate_principal->realm;
self.auth = estrdup("Kerberos");
ret = _krb5_s4u2self_to_checksumdata(context, &self, &data);
if (ret) {
free(self.auth);
goto out;
}
ret = krb5_crypto_init(context, &krbtgt->session, 0, &crypto);
if (ret) {
free(self.auth);
krb5_data_free(&data);
goto out;
}
ret = krb5_create_checksum(context,
crypto,
KRB5_KU_OTHER_CKSUM,
0,
data.data,
data.length,
&self.cksum);
krb5_crypto_destroy(context, crypto);
krb5_data_free(&data);
if (ret) {
free(self.auth);
goto out;
}
ASN1_MALLOC_ENCODE(PA_S4U2Self, buf, len, &self, &size, ret);
free(self.auth);
free_Checksum(&self.cksum);
if (ret)
goto out;
if (len != size)
krb5_abortx(context, "internal asn1 error");
ret = krb5_padata_add(context, &padata, KRB5_PADATA_FOR_USER, buf, len);
if (ret)
goto out;
}
ret = init_tgs_req (context,
id,
addresses,
flags,
second_ticket,
in_creds,
krbtgt,
nonce,
&padata,
&subkey,
&req);
if (ret)
goto out;
ASN1_MALLOC_ENCODE(TGS_REQ, enc.data, enc.length, &req, &len, ret);
if (ret)
goto out;
if(enc.length != len)
krb5_abortx(context, "internal error in ASN.1 encoder");
/* don't free addresses */
req.req_body.addresses = NULL;
free_TGS_REQ(&req);
/*
* Send and receive
*/
{
krb5_sendto_ctx stctx;
ret = krb5_sendto_ctx_alloc(context, &stctx);
if (ret)
return ret;
krb5_sendto_ctx_set_func(stctx, _krb5_kdc_retry, NULL);
ret = krb5_sendto_context (context, stctx, &enc,
krbtgt->server->name.name_string.val[1],
&resp);
krb5_sendto_ctx_free(context, stctx);
}
if(ret)
goto out;
memset(&rep, 0, sizeof(rep));
if(decode_TGS_REP(resp.data, resp.length, &rep.kdc_rep, &len) == 0) {
unsigned eflags = 0;
ret = krb5_copy_principal(context,
in_creds->client,
&out_creds->client);
if(ret)
goto out2;
ret = krb5_copy_principal(context,
in_creds->server,
&out_creds->server);
if(ret)
goto out2;
/* this should go someplace else */
out_creds->times.endtime = in_creds->times.endtime;
/* XXX should do better testing */
if (flags.b.constrained_delegation || impersonate_principal)
eflags |= EXTRACT_TICKET_ALLOW_CNAME_MISMATCH;
ret = _krb5_extract_ticket(context,
&rep,
out_creds,
&krbtgt->session,
NULL,
0,
&krbtgt->addresses,
nonce,
eflags,
decrypt_tkt_with_subkey,
subkey);
out2:
krb5_free_kdc_rep(context, &rep);
} else if(krb5_rd_error(context, &resp, &error) == 0) {
ret = krb5_error_from_rd_error(context, &error, in_creds);
krb5_free_error_contents(context, &error);
} else if(resp.length > 0 && ((char*)resp.data)[0] == 4) {
ret = KRB5KRB_AP_ERR_V4_REPLY;
krb5_clear_error_message(context);
} else {
ret = KRB5KRB_AP_ERR_MSG_TYPE;
krb5_clear_error_message(context);
}
out:
if (second_ticket == &second_ticket_data)
free_Ticket(&second_ticket_data);
free_METHOD_DATA(&padata);
krb5_data_free(&resp);
krb5_data_free(&enc);
if(subkey)
krb5_free_keyblock(context, subkey);
return ret;
}
static krb5_error_code
get_cred_kdc_usage(krb5_context context,
krb5_ccache id,
krb5_kdc_flags flags,
krb5_addresses *addresses,
krb5_creds *in_creds,
krb5_creds *krbtgt,
krb5_creds *out_creds,
krb5_key_usage usage)
{
TGS_REQ req;
krb5_data enc;
krb5_data resp;
krb5_kdc_rep rep;
KRB_ERROR error;
krb5_error_code ret;
unsigned nonce;
krb5_keyblock *subkey = NULL;
size_t len;
Ticket second_ticket;
int send_to_kdc_flags = 0;
krb5_data_zero(&resp);
krb5_data_zero(&enc);
krb5_generate_random_block(&nonce, sizeof(nonce));
nonce &= 0xffffffff;
if(flags.b.enc_tkt_in_skey){
ret = decode_Ticket(in_creds->second_ticket.data,
in_creds->second_ticket.length,
&second_ticket, &len);
if(ret)
return ret;
}
ret = init_tgs_req (context,
id,
addresses,
flags,
flags.b.enc_tkt_in_skey ? &second_ticket : NULL,
in_creds,
krbtgt,
nonce,
&subkey,
&req,
usage);
if(flags.b.enc_tkt_in_skey)
free_Ticket(&second_ticket);
if (ret)
goto out;
ASN1_MALLOC_ENCODE(TGS_REQ, enc.data, enc.length, &req, &len, ret);
if (ret)
goto out;
if(enc.length != len)
krb5_abortx(context, "internal error in ASN.1 encoder");
/* don't free addresses */
req.req_body.addresses = NULL;
free_TGS_REQ(&req);
/*
* Send and receive
*/
again:
ret = krb5_sendto_kdc_flags (context, &enc,
&krbtgt->server->name.name_string.val[1],
&resp,
send_to_kdc_flags);
if(ret)
goto out;
memset(&rep, 0, sizeof(rep));
if(decode_TGS_REP(resp.data, resp.length, &rep.kdc_rep, &len) == 0){
ret = krb5_copy_principal(context,
in_creds->client,
&out_creds->client);
if(ret)
goto out;
ret = krb5_copy_principal(context,
in_creds->server,
&out_creds->server);
if(ret)
goto out;
/* this should go someplace else */
out_creds->times.endtime = in_creds->times.endtime;
ret = _krb5_extract_ticket(context,
&rep,
out_creds,
&krbtgt->session,
NULL,
KRB5_KU_TGS_REP_ENC_PART_SESSION,
&krbtgt->addresses,
nonce,
TRUE,
flags.b.request_anonymous,
decrypt_tkt_with_subkey,
subkey);
krb5_free_kdc_rep(context, &rep);
} else if(krb5_rd_error(context, &resp, &error) == 0) {
ret = krb5_error_from_rd_error(context, &error, in_creds);
krb5_free_error_contents(context, &error);
if (ret == KRB5KRB_ERR_RESPONSE_TOO_BIG && !(send_to_kdc_flags & KRB5_KRBHST_FLAGS_LARGE_MSG)) {
send_to_kdc_flags |= KRB5_KRBHST_FLAGS_LARGE_MSG;
krb5_data_free(&resp);
goto again;
}
} else if(resp.data && ((char*)resp.data)[0] == 4) {
ret = KRB5KRB_AP_ERR_V4_REPLY;
krb5_clear_error_string(context);
} else {
ret = KRB5KRB_AP_ERR_MSG_TYPE;
krb5_clear_error_string(context);
}
out:
krb5_data_free(&resp);
krb5_data_free(&enc);
if(subkey){
krb5_free_keyblock_contents(context, subkey);
free(subkey);
}
return ret;
}