MFC: following 2 commits:

[dragonfly.git] / usr.sbin / atm / scspd / scsp_subr.c

/*
 *
 * ===================================
 * HARP  |  Host ATM Research Platform
 * ===================================
 *
 *
 * This Host ATM Research Platform ("HARP") file (the "Software") is
 * made available by Network Computing Services, Inc. ("NetworkCS")
 * "AS IS".  NetworkCS does not provide maintenance, improvements or
 * support of any kind.
 *
 * NETWORKCS MAKES NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED,
 * INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE, AS TO ANY ELEMENT OF THE
 * SOFTWARE OR ANY SUPPORT PROVIDED IN CONNECTION WITH THIS SOFTWARE.
 * In no event shall NetworkCS be responsible for any damages, including
 * but not limited to consequential damages, arising from or relating to
 * any use of the Software or related support.
 *
 * Copyright 1994-1998 Network Computing Services, Inc.
 *
 * Copies of this Software may be made, however, the above copyright
 * notice must be reproduced on all copies.
 *
 *      @(#) $FreeBSD: src/usr.sbin/atm/scspd/scsp_subr.c,v 1.3 1999/08/28 01:15:34 peter Exp $
 *      @(#) $DragonFly: src/usr.sbin/atm/scspd/scsp_subr.c,v 1.4 2004/12/18 22:48:02 swildner Exp $
 */


/*
 * Server Cache Synchronization Protocol (SCSP) Support
 * ----------------------------------------------------
 *
 * SCSP subroutines
 *
 */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netatm/port.h> 
#include <netatm/queue.h> 
#include <netatm/atm.h>
#include <netatm/atm_if.h>
#include <netatm/atm_sap.h>
#include <netatm/atm_sigmgr.h>
#include <netatm/atm_sys.h>
#include <netatm/atm_ioctl.h>
#include <netatm/uni/unisig_var.h>

#include <errno.h>
#include <libatm.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>

#include "scsp_msg.h"
#include "scsp_if.h"
#include "scsp_var.h"

/*
 * Hash an SCSP cache key
 *
 * Arguments:
 *      ckp     pointer to an SCSP cache key structure
 *
 * Returns:
 *      hashed value
 *
 */
int
scsp_hash(Scsp_ckey *ckp)
{
        int     i, j, h;

        /*
         * Turn cache key into a positive integer
         */
        h = 0;
        for (i = ckp->key_len-1, j = 0;
                        i > 0 && j < sizeof(int);
                        i--, j++)
                h = (h << 8) + ckp->key[i];
        h = abs(h);

        /*
         * Return the hashed value
         */
        return(h % SCSP_HASHSZ);
}


/*
 * Compare two SCSP IDs
 *
 * Arguments:
 *      id1p    pointer to an SCSP ID structure
 *      id2p    pointer to an SCSP ID structure
 *
 * Returns:
 *      < 0     id1 is less than id2
 *      0       id1 and id2 are equal
 *      > 0     id1 is greater than id2
 *
 */
int
scsp_cmp_id(Scsp_id *id1p, Scsp_id *id2p)
{
        int     diff, i;

        /*
         * Compare the two IDs, byte for byte
         */
        for (i = 0; i < id1p->id_len && i < id2p->id_len; i++) {
                diff = id1p->id[i] - id2p->id[i];
                if (diff) {
                        return(diff);
                }
        }

        /*
         * IDs are equal.  If lengths differ, the longer ID is
         * greater than the shorter.
         */
        return(id1p->id_len - id2p->id_len);
}


/*
 * Compare two SCSP cache keys
 *
 * Arguments:
 *      ck1p    pointer to an SCSP cache key structure
 *      ck2p    pointer to an SCSP cache key structure
 *
 * Returns:
 *      < 0     ck1 is less than ck2
 *      0       ck1 and ck2 are equal
 *      > 0     ck1 is greater than ck2
 *
 */
int
scsp_cmp_key(Scsp_ckey *ck1p, Scsp_ckey *ck2p)
{
        int     diff, i;

        /*
         * Compare the two keys, byte for byte
         */
        for (i = 0; i < ck1p->key_len && i < ck2p->key_len; i++) {
                diff = ck1p->key[i] - ck2p->key[i];
                if (diff)
                        return(diff);
        }

        /*
         * Keys are equal.  If lengths differ, the longer key is
         * greater than the shorter.
         */
        return(ck1p->key_len - ck2p->key_len);
}


/*
 * Check whether the host system is an ATMARP server for
 * the LIS associated with a given interface
 *
 * Arguments:
 *      netif   pointer to the network interface name
 *
 * Returns:
 *      1       host is a server
 *      0       host is not a server
 *
 */
int
scsp_is_atmarp_server(char *netif)
{
        int                     rc;
        int                     buf_len = sizeof(struct air_asrv_rsp);
        struct atminfreq        air;
        struct air_asrv_rsp     *asrv_info;

        /*
         * Get interface information from the kernel
         */
        strcpy(air.air_int_intf, netif);
        air.air_opcode = AIOCS_INF_ASV;
        buf_len = do_info_ioctl(&air, buf_len);
        if (buf_len < 0)
                return(0);

        /*
         * Check the interface's ATMARP server address
         */
        asrv_info = (struct air_asrv_rsp *) air.air_buf_addr;
        rc = (asrv_info->asp_addr.address_format == T_ATM_ABSENT) &&
                        (asrv_info->asp_subaddr.address_format ==
                                T_ATM_ABSENT);
        UM_FREE(asrv_info);
        return(rc);
}


/*
 * Make a copy of a cache summary entry
 *
 * Arguments:
 *      csep    pointer to CSE entry to copy
 *
 * Returns:
 *      0       copy failed
 *      else    pointer to new CSE entry
 *
 */
Scsp_cse *
scsp_dup_cse(Scsp_cse *csep)
{
        Scsp_cse        *dupp;

        /*
         * Allocate memory for the duplicate
         */
        dupp = (Scsp_cse *)UM_ALLOC(sizeof(Scsp_cse));
        if (!dupp) {
                scsp_mem_err("scsp_dup_cse: sizeof(Scsp_cse)");
        }

        /*
         * Copy data to the duplicate
         */
        UM_COPY(csep, dupp, sizeof(Scsp_cse));
        dupp->sc_next = (Scsp_cse *)0;

        return(dupp);
}


/*
 * Make a copy of a CSA or CSAS record
 *
 * Arguments:
 *      csap    pointer to CSE entry to copy
 *
 * Returns:
 *      0       copy failed
 *      else    pointer to new CSA or CSAS record
 *
 */
Scsp_csa *
scsp_dup_csa(Scsp_csa *csap)
{
        Scsp_csa        *dupp;
        Scsp_atmarp_csa *adp;

        /*
         * Allocate memory for the duplicate
         */
        dupp = (Scsp_csa *)UM_ALLOC(sizeof(Scsp_csa));
        if (!dupp) {
                scsp_mem_err("scsp_dup_csa: sizeof(Scsp_csa)");
        }

        /*
         * Copy data to the duplicate
         */
        UM_COPY(csap, dupp, sizeof(Scsp_csa));
        dupp->next = (Scsp_csa *)0;

        /*
         * Copy protocol-specific data, if it's present
         */
        if (csap->atmarp_data) {
                adp = (Scsp_atmarp_csa *)UM_ALLOC(sizeof(Scsp_atmarp_csa));
                if (!adp) {
                        scsp_mem_err("scsp_dup_csa: sizeof(Scsp_atmarp_csa)");
                }
                UM_COPY(csap->atmarp_data, adp, sizeof(Scsp_atmarp_csa));
                dupp->atmarp_data  = adp;
        }

        return(dupp);
}


/*
 * Copy a cache summary entry into a CSAS
 *
 * Arguments:
 *      csep    pointer to CSE entry to copy
 *
 * Returns:
 *      0       copy failed
 *      else    pointer to CSAS record summarizing the entry
 *
 */
Scsp_csa *
scsp_cse2csas(Scsp_cse *csep)
{
        Scsp_csa        *csap;

        /*
         * Allocate memory for the duplicate
         */
        csap = (Scsp_csa *)UM_ALLOC(sizeof(Scsp_csa));
        if (!csap) {
                scsp_mem_err("scsp_cse2csas: sizeof(Scsp_csa)");
        }
        UM_ZERO(csap, sizeof(Scsp_csa));

        /*
         * Copy data to the CSAS entry
         */
        csap->seq = csep->sc_seq;
        csap->key = csep->sc_key;
        csap->oid = csep->sc_oid;

        return(csap);
}


/*
 * Copy an ATMARP cache entry into a cache summary entry
 *
 * Arguments:
 *      aap     pointer to ATMARP cache entry to copy
 *
 * Returns:
 *      0       copy failed
 *      else    pointer to CSE record summarizing the entry
 *
 */
Scsp_cse *
scsp_atmarp2cse(Scsp_atmarp_msg *aap)
{
        Scsp_cse        *csep;

        /*
         * Allocate memory for the duplicate
         */
        csep = (Scsp_cse *)UM_ALLOC(sizeof(Scsp_cse));
        if (!csep) {
                scsp_mem_err("scsp_atmarp2cse: sizeof(Scsp_cse)");
        }
        UM_ZERO(csep, sizeof(Scsp_cse));

        /*
         * Copy data to the CSE entry
         */
        csep->sc_seq = aap->sa_seq;
        csep->sc_key = aap->sa_key;
        csep->sc_oid = aap->sa_oid;

        return(csep);
}


/*
 * Clean up a DCS block.  This routine is called to clear out any
 * lingering state information when the CA FSM reverts to an 'earlier'
 * state (Down or Master/Slave Negotiation).
 *
 * Arguments:
 *      dcsp    pointer to a DCS control block for the neighbor
 *
 * Returns:
 *      none
 *
 */
void
scsp_dcs_cleanup(Scsp_dcs *dcsp)
{
        Scsp_cse        *csep, *ncsep;
        Scsp_csa        *csap, *next_csap;
        Scsp_csu_rexmt  *rxp, *rx_next;

        /*
         * Free any CSAS entries waiting to be sent
         */
        for (csep = dcsp->sd_ca_csas; csep; csep = ncsep) {
                ncsep = csep->sc_next;
                UNLINK(csep, Scsp_cse, dcsp->sd_ca_csas, sc_next);
                UM_FREE(csep);
        }

        /*
         * Free any entries on the CRL
         */
        for (csap = dcsp->sd_crl; csap; csap = next_csap) {
                next_csap = csap->next;
                UNLINK(csap, Scsp_csa, dcsp->sd_crl, next);
                SCSP_FREE_CSA(csap);
        }

        /*
         * Free any saved CA message and cancel the CA
         * retransmission timer
         */
        if (dcsp->sd_ca_rexmt_msg) {
                scsp_free_msg(dcsp->sd_ca_rexmt_msg);
                dcsp->sd_ca_rexmt_msg = (Scsp_msg *)0;
        }
        HARP_CANCEL(&dcsp->sd_ca_rexmt_t);

        /*
         * Free any saved CSU Solicit message and cancel the CSUS
         * retransmission timer
         */
        if (dcsp->sd_csus_rexmt_msg) {
                scsp_free_msg(dcsp->sd_csus_rexmt_msg);
                dcsp->sd_csus_rexmt_msg = (Scsp_msg *)0;
        }
        HARP_CANCEL(&dcsp->sd_csus_rexmt_t);

        /*
         * Free any entries on the CSU Request retransmission queue
         */
        for (rxp = dcsp->sd_csu_rexmt; rxp; rxp = rx_next) {
                rx_next = rxp->sr_next;
                HARP_CANCEL(&rxp->sr_t);
                for (csap = rxp->sr_csa; csap; csap = next_csap) {
                        next_csap = csap->next;
                        SCSP_FREE_CSA(csap);
                }
                UNLINK(rxp, Scsp_csu_rexmt, dcsp->sd_csu_rexmt,
                                sr_next);
                UM_FREE(rxp);
        }
}


/*
 * Delete an SCSP DCS block and any associated information
 *
 * Arguments:
 *      dcsp    pointer to a DCS control block to delete
 *
 * Returns:
 *      none
 *
 */
void
scsp_dcs_delete(Scsp_dcs *dcsp)
{
        Scsp_cse        *csep, *next_cse;
        Scsp_csu_rexmt  *rxp, *next_rxp;
        Scsp_csa        *csap, *next_csa;

        /*
         * Cancel any pending DCS timers
         */
        HARP_CANCEL(&dcsp->sd_open_t);
        HARP_CANCEL(&dcsp->sd_hello_h_t);
        HARP_CANCEL(&dcsp->sd_hello_rcv_t);
        HARP_CANCEL(&dcsp->sd_ca_rexmt_t);
        HARP_CANCEL(&dcsp->sd_csus_rexmt_t);

        /*
         * Unlink the DCS block from the server block
         */
        UNLINK(dcsp, Scsp_dcs, dcsp->sd_server->ss_dcs, sd_next);

        /*
         * Close the VCC to the DCS, if one is open
         */
        if (dcsp->sd_sock != -1) {
                close(dcsp->sd_sock);
        }

        /*
         * Free any saved CA message
         */
        if (dcsp->sd_ca_rexmt_msg) {
                scsp_free_msg(dcsp->sd_ca_rexmt_msg);
        }

        /*
         * Free any pending CSAs waiting for cache alignment
         */
        for (csep = dcsp->sd_ca_csas; csep; csep = next_cse) {
                next_cse = csep->sc_next;
                UM_FREE(csep);
        }

        /*
         * Free anything on the cache request list
         */
        for (csap = dcsp->sd_crl; csap; csap = next_csa) {
                next_csa = csap->next;
                SCSP_FREE_CSA(csap);
        }

        /*
         * Free any saved CSUS message
         */
        if (dcsp->sd_csus_rexmt_msg) {
                scsp_free_msg(dcsp->sd_csus_rexmt_msg);
        }

        /*
         * Free anything on the CSU Request retransmit queue
         */
        for (rxp = dcsp->sd_csu_rexmt; rxp; rxp = next_rxp) {
                /*
                 * Cancel the retransmit timer
                 */
                HARP_CANCEL(&rxp->sr_t);

                /*
                 * Free the CSAs to be retransmitted
                 */
                for (csap = rxp->sr_csa; csap; csap = next_csa) {
                        next_csa = csap->next;
                        SCSP_FREE_CSA(csap);
                }

                /*
                 * Free the CSU Req retransmission control block
                 */
                next_rxp = rxp->sr_next;
                UM_FREE(rxp);
        }

        /*
         * Free the DCS block
         */
        UM_FREE(dcsp);
}


/*
 * Shut down a server.  This routine is called when a connection to
 * a server is lost.  It will clear the server's state without deleting
 * the server.
 *
 * Arguments:
 *      ssp     pointer to a server control block
 *
 * Returns:
 *      none
 *
 */
void
scsp_server_shutdown(Scsp_server *ssp)
{
        int             i;
        Scsp_dcs        *dcsp;
        Scsp_cse        *csep;

        /*
         * Trace the shutdown
         */
        if (scsp_trace_mode & (SCSP_TRACE_IF_MSG | SCSP_TRACE_CFSM)) {
                scsp_trace("Server %s being shut down\n",
                                ssp->ss_name);
        }

        /*
         * Terminate up all the DCS connections and clean
         * up the control blocks
         */
        for (dcsp = ssp->ss_dcs; dcsp; dcsp = dcsp->sd_next) {
                if (dcsp->sd_sock != -1) {
                        close(dcsp->sd_sock);
                        dcsp->sd_sock = -1;
                }
                HARP_CANCEL(&dcsp->sd_open_t);
                HARP_CANCEL(&dcsp->sd_hello_h_t);
                HARP_CANCEL(&dcsp->sd_hello_rcv_t);
                scsp_dcs_cleanup(dcsp);
                dcsp->sd_hello_state = SCSP_HFSM_DOWN;
                dcsp->sd_ca_state = SCSP_CAFSM_DOWN;
                dcsp->sd_client_state = SCSP_CIFSM_NULL;
        }

        /*
         * Clean up the server control block
         */
        if (ssp->ss_sock != -1) {
                close(ssp->ss_sock);
                ssp->ss_sock = -1;
        }
        if (ssp->ss_dcs_lsock != -1) {
                close(ssp->ss_dcs_lsock);
                ssp->ss_dcs_lsock = -1;
        }
        ssp->ss_state = SCSP_SS_NULL;

        /*
         * Free the entries in the server's summary cache
         */
        for (i = 0; i < SCSP_HASHSZ; i++) {
                while (ssp->ss_cache[i]) {
                        csep = ssp->ss_cache[i];
                        UNLINK(csep, Scsp_cse, ssp->ss_cache[i],
                                        sc_next);
                        UM_FREE(csep);
                }
        }
}


/*
 * Delete an SCSP server block and any associated information
 *
 * Arguments:
 *      ssp     pointer to a server control block to delete
 *
 * Returns:
 *      none
 *
 */
void
scsp_server_delete(Scsp_server *ssp)
{
        int             i;
        Scsp_dcs        *dcsp, *next_dcs;
        Scsp_cse        *csep, *next_cse;

        /*
         * Unlink the server block from the chain
         */
        UNLINK(ssp, Scsp_server, scsp_server_head, ss_next);

        /*
         * Free the DCS blocks associated with the server
         */
        for (dcsp = ssp->ss_dcs; dcsp; dcsp = next_dcs) {
                next_dcs = dcsp->sd_next;
                scsp_dcs_delete(dcsp);
        }

        /*
         * Free the entries in the server's summary cache
         */
        for (i = 0; i < SCSP_HASHSZ; i++) {
                for (csep = ssp->ss_cache[i]; csep; csep = next_cse) {
                        next_cse = csep->sc_next;
                        UM_FREE(csep);
                }
        }

        /*
         * Free the server block
         */
        UM_FREE(ssp->ss_name);
        UM_FREE(ssp);
}


/*
 * Get informtion about a server from the kernel
 *
 * Arguments:
 *      ssp     pointer to the server block
 *
 * Returns:
 *      0       server info is OK
 *      errno   server is not ready
 *
 */
int
scsp_get_server_info(Scsp_server *ssp)
{
        int                     i, len, mtu, rc, sel;
        struct atminfreq        air;
        struct air_netif_rsp    *netif_rsp = (struct air_netif_rsp *)0;
        struct air_int_rsp      *intf_rsp = (struct air_int_rsp *)0;
        struct air_cfg_rsp      *cfg_rsp = (struct air_cfg_rsp *)0;
        struct sockaddr_in      *ip_addr;
        Atm_addr_nsap           *anp;

        /*
         * Make sure we're the server for the interface
         */
        if (!scsp_is_atmarp_server(ssp->ss_intf)) {
                rc = EINVAL;
                goto server_info_done;
        }

        /*
         * Get the IP address and physical interface name
         * associated with the network interface
         */
        UM_ZERO(&air, sizeof(struct atminfreq));
        air.air_opcode = AIOCS_INF_NIF;
        strcpy(air.air_netif_intf, ssp->ss_intf);
        len = do_info_ioctl(&air, sizeof(struct air_netif_rsp));
        if (len <= 0) {
                rc = EIO;
                goto server_info_done;
        }
        netif_rsp = (struct air_netif_rsp *)air.air_buf_addr;

        ip_addr = (struct sockaddr_in *)&netif_rsp->anp_proto_addr;
        if (ip_addr->sin_family != AF_INET ||
                        ip_addr->sin_addr.s_addr == 0) {
                rc = EADDRNOTAVAIL;
                goto server_info_done;
        }

        /*
         * Get the MTU for the network interface
         */
        mtu = get_mtu(ssp->ss_intf);
        if (mtu < 0) {
                rc = EIO;
                goto server_info_done;
        }

        /*
         * Get the ATM address associated with the
         * physical interface
         */
        UM_ZERO(&air, sizeof(struct atminfreq));
        air.air_opcode = AIOCS_INF_INT;
        strcpy(air.air_int_intf, netif_rsp->anp_phy_intf);
        len = do_info_ioctl(&air, sizeof(struct air_int_rsp));
        if (len <= 0) {
                rc = EIO;
                goto server_info_done;
        }
        intf_rsp = (struct air_int_rsp *)air.air_buf_addr;

        /*
         * Make sure we're running UNI signalling
         */
        if (intf_rsp->anp_sig_proto != ATM_SIG_UNI30 &&
                        intf_rsp->anp_sig_proto != ATM_SIG_UNI31 &&
                        intf_rsp->anp_sig_proto != ATM_SIG_UNI40) {
                rc = EINVAL;
                goto server_info_done;
        }

        /*
         * Check the physical interface's state
         */
        if (intf_rsp->anp_sig_state != UNISIG_ACTIVE) {
                rc = EHOSTDOWN;
                goto server_info_done;
        }

        /*
         * Make sure the interface's address is valid
         */
        if (intf_rsp->anp_addr.address_format != T_ATM_ENDSYS_ADDR &&
                        !(intf_rsp->anp_addr.address_format ==
                                T_ATM_E164_ADDR &&
                        intf_rsp->anp_subaddr.address_format ==
                                T_ATM_ENDSYS_ADDR)) {
                rc = EINVAL;
                goto server_info_done;
        }

        /*
         * Find the selector byte value for the interface
         */
        for (i=0; i<strlen(ssp->ss_intf); i++) {
                if (ssp->ss_intf[i] >= '0' &&
                                ssp->ss_intf[i] <= '9')
                        break;
        }
        sel = atoi(&ssp->ss_intf[i]);

        /*
         * Get configuration information associated with the
         * physical interface
         */
        UM_ZERO(&air, sizeof(struct atminfreq));
        air.air_opcode = AIOCS_INF_CFG;
        strcpy(air.air_int_intf, netif_rsp->anp_phy_intf);
        len = do_info_ioctl(&air, sizeof(struct air_cfg_rsp));
        if (len <= 0) {
                rc = EIO;
                goto server_info_done;
        }
        cfg_rsp = (struct air_cfg_rsp *)air.air_buf_addr;

        /*
         * Update the server entry
         */
        UM_COPY(&ip_addr->sin_addr, ssp->ss_lsid.id, ssp->ss_id_len);
        ssp->ss_lsid.id_len = ssp->ss_id_len;
        ssp->ss_mtu = mtu + 8;
        ATM_ADDR_COPY(&intf_rsp->anp_addr, &ssp->ss_addr);
        ATM_ADDR_COPY(&intf_rsp->anp_subaddr, &ssp->ss_subaddr);
        if (ssp->ss_addr.address_format == T_ATM_ENDSYS_ADDR) {
                anp = (Atm_addr_nsap *)ssp->ss_addr.address;
                anp->aan_sel = sel;
        } else if (ssp->ss_addr.address_format == T_ATM_E164_ADDR &&
                        ssp->ss_subaddr.address_format ==
                                T_ATM_ENDSYS_ADDR) {
                anp = (Atm_addr_nsap *)ssp->ss_subaddr.address;
                anp->aan_sel = sel;
        }
        ssp->ss_media = cfg_rsp->acp_cfg.ac_media;
        rc = 0;

        /*
         * Free dynamic data
         */
server_info_done:
        if (netif_rsp)
                UM_FREE(netif_rsp);
        if (intf_rsp)
                UM_FREE(intf_rsp);
        if (cfg_rsp)
                UM_FREE(cfg_rsp);

        return(rc);
}


/*
 * Process a CA message
 *
 * Arguments:
 *      dcsp    pointer to a DCS control block for the neighbor
 *      cap     pointer to the CA part of the received message
 *
 * Returns:
 *      none
 *
 */
void
scsp_process_ca(Scsp_dcs* dcsp, Scsp_ca *cap)
{
        Scsp_csa        *csap, *next_csap;
        Scsp_cse        *csep;
        Scsp_server     *ssp = dcsp->sd_server;

        /*
         * Process CSAS records from the CA message
         */
        for (csap = cap->ca_csa_rec; csap; csap = next_csap) {
                next_csap = csap->next;
                SCSP_LOOKUP(ssp, &csap->key, csep);
                if (!csep || (scsp_cmp_id(&csap->oid,
                                        &csep->sc_oid) == 0 &&
                                csap->seq > csep->sc_seq)) {
                        /*
                         * CSAS entry not in cache or more
                         * up to date than cache, add it to CRL
                         */
                        UNLINK(csap, Scsp_csa, cap->ca_csa_rec, next);
                        LINK2TAIL(csap, Scsp_csa, dcsp->sd_crl, next);
                }
        }
}


/*
 * Process a Cache Response message from a server
 *
 * Arguments:
 *      ssp     pointer to the server block
 *      smp     pointer to the message
 *
 * Returns:
 *      none
 *
 */
void
scsp_process_cache_rsp(Scsp_server *ssp, Scsp_if_msg *smp)
{
        int             len;
        Scsp_atmarp_msg *aap;
        Scsp_cse        *csep;

        /*
         * Loop through the message, processing each cache entry
         */
        len = smp->si_len;
        len -= sizeof(Scsp_if_msg_hdr);
        aap = &smp->si_atmarp;
        while (len > 0) {
                switch(smp->si_proto) {
                case SCSP_ATMARP_PROTO:
                        /*
                         * If we already have an entry with this key,
                         * delete it
                         */
                        SCSP_LOOKUP(ssp, &aap->sa_key, csep);
                        if (csep) {
                                SCSP_DELETE(ssp, csep);
                                UM_FREE(csep);
                        }

                        /*
                         * Copy the data from the server to a cache
                         * summary entry
                         */
                        csep = scsp_atmarp2cse(aap);

                        /*
                         * Point past this entry
                         */
                        len -= sizeof(Scsp_atmarp_msg);
                        aap++;
                        break;
                case SCSP_NHRP_PROTO:
                default:
                        /*
                         * Not implemented yet
                         */
                        return;
                }

                /*
                 * Add the new summary entry to the cache
                 */
                SCSP_ADD(ssp, csep);
        }
}


/*
 * Propagate a CSA to all the DCSs in the server group except
 * the one the CSA was received from
 *
 * Arguments:
 *      dcsp    pointer to a the DCS the CSA came from
 *      csap    pointer to a the CSA
 *
 * Returns:
 *      0       success
 *      errno   error encountered
 *
 */
int
scsp_propagate_csa(Scsp_dcs *dcsp, Scsp_csa *csap)
{
        int             rc, ret_rc = 0;
        Scsp_server     *ssp = dcsp->sd_server;
        Scsp_dcs        *dcsp1;
        Scsp_csa        *csap1;

        /*
         * Check the hop count in the CSA
         */
        if (csap->hops <= 1)
                return(0);

        /*
         * Pass the cache entry on to the server's other DCSs
         */
        for (dcsp1 = ssp->ss_dcs; dcsp1; dcsp1 = dcsp1->sd_next) {
                /*
                 * Skip this DCS if it's the one we got
                 * the entry from
                 */
                if (dcsp1 == dcsp)
                        continue;

                /*
                 * Copy the  CSA
                 */
                csap1 = scsp_dup_csa(csap);

                /*
                 * Decrement the hop count
                 */
                csap1->hops--;

                /*
                 * Send the copy of the CSA to the CA FSM for the DCS
                 */
                rc = scsp_cafsm(dcsp1, SCSP_CAFSM_CACHE_UPD,
                                (void *) csap1);
                if (rc)
                        ret_rc = rc;
        }

        return(ret_rc);
}


/*
 * Update SCSP's cache given a CSA or CSAS
 *
 * Arguments:
 *      dcsp    pointer to a DCS 
 *      csap    pointer to a CSA
 *
 * Returns:
 *      none
 *
 */
void
scsp_update_cache(Scsp_dcs *dcsp, Scsp_csa *csap)
{
        Scsp_cse        *csep;

        /*
         * Check whether we already have this in the cache
         */
        SCSP_LOOKUP(dcsp->sd_server, &csap->key, csep);

        /*
         * If we don't already have it and it's not being deleted,
         * build a new cache summary entry
         */
        if (!csep && !csap->null) {
                /*
                 * Get memory for a new entry
                 */
                csep = (Scsp_cse *)UM_ALLOC(sizeof(Scsp_cse));
                if (!csep) {
                        scsp_mem_err("scsp_update_cache: sizeof(Scsp_cse)");
                }
                UM_ZERO(csep, sizeof(Scsp_cse));

                /*
                 * Fill out the new cache summary entry
                 */
                csep->sc_seq = csap->seq;
                csep->sc_key = csap->key;
                csep->sc_oid = csap->oid;

                /*
                 * Add the new entry to the cache
                 */
                SCSP_ADD(dcsp->sd_server, csep);
        } 

        /*
         * Update or delete the entry
         */
        if (csap->null) {
                /*
                 * The null flag is set--delete the entry
                 */
                if (csep) {
                        SCSP_DELETE(dcsp->sd_server, csep);
                        UM_FREE(csep);
                }
        } else {
                /*
                 * Update the existing entry
                 */
                csep->sc_seq = csap->seq;
                csep->sc_oid = csap->oid;
        }
}


/*
 * Reconfigure SCSP
 *
 * Called as the result of a SIGHUP interrupt.  Reread the
 * configuration file and solicit the cache from the server.
 *
 * Arguments:
 *      none
 *
 * Returns:
 *      none
 *
 */
void
scsp_reconfigure(void)
{
        int             rc;
        Scsp_server     *ssp;

        /*
         * Log a message saying we're reconfiguring
         */
        scsp_log(LOG_ERR, "Reconfiguring ...");

        /*
         * Re-read the configuration file
         */
        rc = scsp_config(scsp_config_file);
        if (rc) {
                scsp_log(LOG_ERR, "Found %d error%s in configuration file",
                                rc, ((rc == 1) ? "" : "s"));
                exit(1);
        }

        /*
         * If a connection to a server is open, get the cache from
         * the server
         */
        for (ssp = scsp_server_head; ssp; ssp = ssp->ss_next) {
                if (ssp->ss_sock != -1) {
                        rc = scsp_send_cache_ind(ssp);
                }
        }
}