static void
test_ap(krb5_context context,
krb5_principal sprincipal,
krb5_keytab keytab,
krb5_ccache ccache,
const krb5_flags client_flags)
{
krb5_error_code ret;
krb5_auth_context client_ac = NULL, server_ac = NULL;
krb5_data data;
krb5_flags server_flags;
krb5_ticket *ticket = NULL;
int32_t server_seq, client_seq;
ret = krb5_mk_req_exact(context,
&client_ac,
client_flags,
sprincipal,
NULL,
ccache,
&data);
if (ret)
krb5_err(context, 1, ret, "krb5_mk_req_exact");
ret = krb5_rd_req(context,
&server_ac,
&data,
sprincipal,
keytab,
&server_flags,
&ticket);
if (ret)
krb5_err(context, 1, ret, "krb5_rd_req");
if (server_flags & AP_OPTS_MUTUAL_REQUIRED) {
krb5_ap_rep_enc_part *repl;
krb5_data_free(&data);
if ((client_flags & AP_OPTS_MUTUAL_REQUIRED) == 0)
krb5_errx(context, 1, "client flag missing mutual req");
ret = krb5_mk_rep (context, server_ac, &data);
if (ret)
krb5_err(context, 1, ret, "krb5_mk_rep");
ret = krb5_rd_rep (context,
client_ac,
&data,
&repl);
if (ret)
krb5_err(context, 1, ret, "krb5_rd_rep");
krb5_free_ap_rep_enc_part (context, repl);
} else {
if (client_flags & AP_OPTS_MUTUAL_REQUIRED)
krb5_errx(context, 1, "server flag missing mutual req");
}
krb5_auth_getremoteseqnumber(context, server_ac, &server_seq);
krb5_auth_getremoteseqnumber(context, client_ac, &client_seq);
if (server_seq != client_seq)
krb5_errx(context, 1, "seq num differ");
krb5_auth_con_getlocalseqnumber(context, server_ac, &server_seq);
krb5_auth_con_getlocalseqnumber(context, client_ac, &client_seq);
if (server_seq != client_seq)
krb5_errx(context, 1, "seq num differ");
krb5_data_free(&data);
krb5_auth_con_free(context, client_ac);
krb5_auth_con_free(context, server_ac);
if (verify_pac) {
krb5_pac pac;
ret = krb5_ticket_get_authorization_data_type(context,
ticket,
KRB5_AUTHDATA_WIN2K_PAC,
&data);
if (ret)
krb5_err(context, 1, ret, "get pac");
ret = krb5_pac_parse(context, data.data, data.length, &pac);
if (ret)
krb5_err(context, 1, ret, "pac parse");
krb5_pac_free(context, pac);
}
krb5_free_ticket(context, ticket);
}
static krb5_error_code samba_wdc_reget_pac(void *priv, krb5_context context,
const krb5_principal client_principal,
const krb5_principal delegated_proxy_principal,
struct hdb_entry_ex *client,
struct hdb_entry_ex *server,
struct hdb_entry_ex *krbtgt,
krb5_pac *pac)
{
struct samba_kdc_entry *p = talloc_get_type(server->ctx, struct samba_kdc_entry);
TALLOC_CTX *mem_ctx = talloc_named(p, 0, "samba_kdc_reget_pac context");
DATA_BLOB *pac_blob;
DATA_BLOB *deleg_blob = NULL;
krb5_error_code ret;
NTSTATUS nt_status;
struct PAC_SIGNATURE_DATA *pac_srv_sig;
struct PAC_SIGNATURE_DATA *pac_kdc_sig;
bool is_in_db, is_untrusted;
if (!mem_ctx) {
return ENOMEM;
}
/* The user account may be set not to want the PAC */
if (!samba_princ_needs_pac(server)) {
talloc_free(mem_ctx);
return EINVAL;
}
/* If the krbtgt was generated by an RODC, and we are not that
* RODC, then we need to regenerate the PAC - we can't trust
* it */
ret = samba_krbtgt_is_in_db(krbtgt, &is_in_db, &is_untrusted);
if (ret != 0) {
talloc_free(mem_ctx);
return ret;
}
if (is_untrusted) {
if (client == NULL) {
return KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN;
}
nt_status = samba_kdc_get_pac_blob(mem_ctx, client, &pac_blob);
if (!NT_STATUS_IS_OK(nt_status)) {
talloc_free(mem_ctx);
return EINVAL;
}
} else {
pac_blob = talloc_zero(mem_ctx, DATA_BLOB);
if (!pac_blob) {
talloc_free(mem_ctx);
return ENOMEM;
}
pac_srv_sig = talloc_zero(mem_ctx, struct PAC_SIGNATURE_DATA);
if (!pac_srv_sig) {
talloc_free(mem_ctx);
return ENOMEM;
}
pac_kdc_sig = talloc_zero(mem_ctx, struct PAC_SIGNATURE_DATA);
if (!pac_kdc_sig) {
talloc_free(mem_ctx);
return ENOMEM;
}
nt_status = samba_kdc_update_pac_blob(mem_ctx, context,
*pac, pac_blob,
pac_srv_sig, pac_kdc_sig);
if (!NT_STATUS_IS_OK(nt_status)) {
DEBUG(0, ("Building PAC failed: %s\n",
nt_errstr(nt_status)));
talloc_free(mem_ctx);
return EINVAL;
}
if (is_in_db) {
/* Now check the KDC signature, fetching the correct key based on the enc type */
ret = kdc_check_pac(context, pac_srv_sig->signature, pac_kdc_sig, krbtgt);
if (ret != 0) {
DEBUG(1, ("PAC KDC signature failed to verify\n"));
talloc_free(mem_ctx);
return ret;
}
}
}
if (delegated_proxy_principal) {
deleg_blob = talloc_zero(mem_ctx, DATA_BLOB);
if (!deleg_blob) {
talloc_free(mem_ctx);
return ENOMEM;
}
nt_status = samba_kdc_update_delegation_info_blob(mem_ctx,
context, *pac,
server->entry.principal,
delegated_proxy_principal,
deleg_blob);
if (!NT_STATUS_IS_OK(nt_status)) {
DEBUG(0, ("Building PAC failed: %s\n",
nt_errstr(nt_status)));
talloc_free(mem_ctx);
return EINVAL;
}
}
/* We now completely regenerate this pac */
krb5_pac_free(context, *pac);
ret = samba_make_krb5_pac(context, pac_blob, deleg_blob, pac);
talloc_free(mem_ctx);
return ret;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_ctx(krb5_context context,
krb5_auth_context *auth_context,
const krb5_data *inbuf,
krb5_const_principal server,
krb5_rd_req_in_ctx inctx,
krb5_rd_req_out_ctx *outctx)
{
krb5_error_code ret;
krb5_ap_req ap_req;
krb5_rd_req_out_ctx o = NULL;
krb5_keytab id = NULL, keytab = NULL;
krb5_principal service = NULL;
*outctx = NULL;
o = calloc(1, sizeof(*o));
if (o == NULL)
return krb5_enomem(context);
if (*auth_context == NULL) {
ret = krb5_auth_con_init(context, auth_context);
if (ret)
goto out;
}
ret = krb5_decode_ap_req(context, inbuf, &ap_req);
if(ret)
goto out;
/* Save the principal that was in the request */
ret = _krb5_principalname2krb5_principal(context,
&o->server,
ap_req.ticket.sname,
ap_req.ticket.realm);
if (ret)
goto out;
if (ap_req.ap_options.use_session_key &&
(*auth_context)->keyblock == NULL) {
ret = KRB5KRB_AP_ERR_NOKEY;
krb5_set_error_message(context, ret,
N_("krb5_rd_req: user to user auth "
"without session key given", ""));
goto out;
}
if (inctx && inctx->keytab)
id = inctx->keytab;
if((*auth_context)->keyblock){
ret = krb5_copy_keyblock(context,
(*auth_context)->keyblock,
&o->keyblock);
if (ret)
goto out;
} else if(inctx && inctx->keyblock){
ret = krb5_copy_keyblock(context,
inctx->keyblock,
&o->keyblock);
if (ret)
goto out;
} else {
if(id == NULL) {
krb5_kt_default(context, &keytab);
id = keytab;
}
if (id == NULL)
goto out;
if (server == NULL) {
ret = _krb5_principalname2krb5_principal(context,
&service,
ap_req.ticket.sname,
ap_req.ticket.realm);
if (ret)
goto out;
server = service;
}
ret = get_key_from_keytab(context,
&ap_req,
server,
id,
&o->keyblock);
if (ret) {
/* If caller specified a server, fail. */
if (service == NULL && (context->flags & KRB5_CTX_F_RD_REQ_IGNORE) == 0)
goto out;
/* Otherwise, fall back to iterating over the keytab. This
* have serious performace issues for larger keytab.
*/
o->keyblock = NULL;
}
}
if (o->keyblock) {
/*
* We got an exact keymatch, use that.
*/
ret = krb5_verify_ap_req2(context,
auth_context,
&ap_req,
server,
o->keyblock,
0,
&o->ap_req_options,
&o->ticket,
KRB5_KU_AP_REQ_AUTH);
if (ret)
goto out;
} else {
/*
* Interate over keytab to find a key that can decrypt the request.
*/
krb5_keytab_entry entry;
krb5_kt_cursor cursor;
int done = 0, kvno = 0;
memset(&cursor, 0, sizeof(cursor));
if (ap_req.ticket.enc_part.kvno)
kvno = *ap_req.ticket.enc_part.kvno;
ret = krb5_kt_start_seq_get(context, id, &cursor);
if (ret)
goto out;
done = 0;
while (!done) {
krb5_principal p;
ret = krb5_kt_next_entry(context, id, &entry, &cursor);
if (ret) {
_krb5_kt_principal_not_found(context, ret, id, o->server,
ap_req.ticket.enc_part.etype,
kvno);
break;
}
if (entry.keyblock.keytype != ap_req.ticket.enc_part.etype) {
krb5_kt_free_entry (context, &entry);
continue;
}
ret = krb5_verify_ap_req2(context,
auth_context,
&ap_req,
server,
&entry.keyblock,
0,
&o->ap_req_options,
&o->ticket,
KRB5_KU_AP_REQ_AUTH);
if (ret) {
krb5_kt_free_entry (context, &entry);
continue;
}
/*
* Found a match, save the keyblock for PAC processing,
* and update the service principal in the ticket to match
* whatever is in the keytab.
*/
ret = krb5_copy_keyblock(context,
&entry.keyblock,
&o->keyblock);
if (ret) {
krb5_kt_free_entry (context, &entry);
break;
}
ret = krb5_copy_principal(context, entry.principal, &p);
if (ret) {
krb5_kt_free_entry (context, &entry);
break;
}
krb5_free_principal(context, o->ticket->server);
o->ticket->server = p;
krb5_kt_free_entry (context, &entry);
done = 1;
}
krb5_kt_end_seq_get (context, id, &cursor);
if (ret)
goto out;
}
/* If there is a PAC, verify its server signature */
if (inctx == NULL || inctx->check_pac) {
krb5_pac pac;
krb5_data data;
ret = krb5_ticket_get_authorization_data_type(context,
o->ticket,
KRB5_AUTHDATA_WIN2K_PAC,
&data);
if (ret == 0) {
ret = krb5_pac_parse(context, data.data, data.length, &pac);
krb5_data_free(&data);
if (ret)
goto out;
ret = krb5_pac_verify(context,
pac,
o->ticket->ticket.authtime,
o->ticket->client,
o->keyblock,
NULL);
krb5_pac_free(context, pac);
if (ret)
goto out;
} else
ret = 0;
}
out:
if (ret || outctx == NULL) {
krb5_rd_req_out_ctx_free(context, o);
} else
*outctx = o;
free_AP_REQ(&ap_req);
if (service)
krb5_free_principal(context, service);
if (keytab)
krb5_kt_close(context, keytab);
return ret;
}
