responder/pam/pamsrv_dp.c

/*
   SSSD

   NSS Responder - Data Provider Interfaces

   Copyright (C) Simo Sorce <ssorce@redhat.com> 2008

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include <sys/time.h>
#include <time.h>

#include <talloc.h>
#include <security/pam_modules.h>

#include "util/util.h"
#include "responder/common/responder_packet.h"
#include "providers/data_provider.h"
#include "sbus/sbus_client.h"
#include "responder/pam/pamsrv.h"

static void pam_dp_process_reply(DBusPendingCall *pending, void *ptr)
{
    DBusError dbus_error;
    DBusMessage* msg;
    int ret;
    int type;
    struct pam_auth_req *preq = NULL;
    struct pam_auth_dp_req *pdp_req;

    pdp_req = talloc_get_type(ptr, struct pam_auth_dp_req);
    preq = pdp_req->preq;
    talloc_free(pdp_req);

    dbus_error_init(&dbus_error);
    msg = dbus_pending_call_steal_reply(pending);

    /* Check if the client still exists. If not, simply free all the resources
     * and quit */
    if (preq == NULL) {
        DEBUG(SSSDBG_MINOR_FAILURE, "Client already disconnected\n");
        dbus_pending_call_unref(pending);
        dbus_message_unref(msg);
        return;
    }

    /* Sanity-check of message validity */
    if (msg == NULL) {
        DEBUG(SSSDBG_FATAL_FAILURE,
              "Severe error. A reply callback was called but no reply was"
                  "received and no timeout occurred\n");
        preq->pd->pam_status = PAM_SYSTEM_ERR;
        goto done;
    }

    type = dbus_message_get_type(msg);
    switch (type) {
        case DBUS_MESSAGE_TYPE_METHOD_RETURN:
            ret = dp_unpack_pam_response(msg, preq->pd, &dbus_error);
            if (!ret) {
                DEBUG(SSSDBG_FATAL_FAILURE, "Failed to parse reply.\n");
                preq->pd->pam_status = PAM_SYSTEM_ERR;
                goto done;
            }
            DEBUG(SSSDBG_FUNC_DATA,
                  "received: [%d (%s)][%s]\n", preq->pd->pam_status,
                  pam_strerror(NULL, preq->pd->pam_status),
                  preq->pd->domain);
             break;
        case DBUS_MESSAGE_TYPE_ERROR:
            DEBUG(SSSDBG_FATAL_FAILURE, "Reply error.\n");
            preq->pd->pam_status = PAM_SYSTEM_ERR;
            break;
        default:
            DEBUG(SSSDBG_FATAL_FAILURE, "Default... what now?.\n");
            preq->pd->pam_status = PAM_SYSTEM_ERR;
    }


done:
    dbus_pending_call_unref(pending);
    dbus_message_unref(msg);
    preq->callback(preq);
}

static int pdp_req_destructor(struct pam_auth_dp_req *pdp_req)
{
    if (pdp_req && pdp_req->preq) {
        /* If there is still a client waiting, reset the
         * spy */
        pdp_req->preq->dpreq_spy = NULL;
    }
    return 0;
}

int pam_dp_send_req(struct pam_auth_req *preq, int timeout)
{
    struct pam_data *pd = preq->pd;
    struct be_conn *be_conn;
    DBusMessage *msg;
    dbus_bool_t ret;
    int res;
    struct pam_auth_dp_req *pdp_req;

    /* double check dp_ctx has actually been initialized.
     * in some pathological cases it may happen that nss starts up before
     * dp connection code is actually able to establish a connection.
     */
    res = sss_dp_get_domain_conn(preq->cctx->rctx,
                                 preq->domain->conn_name, &be_conn);
    if (res != EOK) {
        DEBUG(SSSDBG_CRIT_FAILURE,
              "The Data Provider connection for %s is not available!"
               " This maybe a bug, it shouldn't happen!\n",
               preq->domain->conn_name);
        return EIO;
    }

    msg = dbus_message_new_method_call(NULL,
                                       DP_PATH,
                                       IFACE_DP,
                                       IFACE_DP_PAMHANDLER);
    if (msg == NULL) {
        DEBUG(SSSDBG_FATAL_FAILURE,"Out of memory?!\n");
        return ENOMEM;
    }


    DEBUG(SSSDBG_CONF_SETTINGS, "Sending request with the following data:\n");
    DEBUG_PAM_DATA(SSSDBG_CONF_SETTINGS, pd);

    ret = dp_pack_pam_request(msg, pd);
    if (!ret) {
        DEBUG(SSSDBG_CRIT_FAILURE,"Failed to build message\n");
        return EIO;
    }

    pdp_req = talloc(preq->cctx->rctx, struct pam_auth_dp_req);
    if (pdp_req == NULL) {
        return ENOMEM;
    }
    pdp_req->preq = preq;
    preq->dpreq_spy = pdp_req;
    talloc_set_destructor(pdp_req, pdp_req_destructor);

    res = sbus_conn_send(be_conn->conn, msg,
                         timeout, pam_dp_process_reply,
                         pdp_req, NULL);
    dbus_message_unref(msg);
    return res;
}