root/sbin/iked/radius.c
/*      $OpenBSD: radius.c,v 1.14 2025/06/24 00:05:42 yasuoka Exp $     */

/*
 * Copyright (c) 2024 Internet Initiative Japan Inc.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <arpa/inet.h>
#include <netinet/ip_ipsp.h>

#include <endian.h>
#include <event.h>
#include <errno.h>
#include <imsg.h>
#include <limits.h>
#include <netinet/in.h>
#include <radius.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <time.h>

#include "iked.h"
#include "eap.h"
#include "ikev2.h"
#include "types.h"

void     iked_radius_request_send(struct iked *, void *);
void     iked_radius_fill_attributes(struct iked_sa *, RADIUS_PACKET *);
void     iked_radius_config(struct iked_radserver_req *, const RADIUS_PACKET *,
            int, uint32_t, uint8_t);
void     iked_radius_acct_request(struct iked *, struct iked_sa *, uint8_t);

const struct iked_radcfgmap radius_cfgmaps[] = {
    { IKEV2_CFG_INTERNAL_IP4_ADDRESS, 0, RADIUS_TYPE_FRAMED_IP_ADDRESS },
    { IKEV2_CFG_INTERNAL_IP4_NETMASK, 0, RADIUS_TYPE_FRAMED_IP_NETMASK },
    { IKEV2_CFG_INTERNAL_IP4_DNS, RADIUS_VENDOR_MICROSOFT,
        RADIUS_VTYPE_MS_PRIMARY_DNS_SERVER },
    { IKEV2_CFG_INTERNAL_IP4_DNS, RADIUS_VENDOR_MICROSOFT,
        RADIUS_VTYPE_MS_SECONDARY_DNS_SERVER },
    { IKEV2_CFG_INTERNAL_IP4_NBNS, RADIUS_VENDOR_MICROSOFT,
        RADIUS_VTYPE_MS_PRIMARY_NBNS_SERVER },
    { IKEV2_CFG_INTERNAL_IP4_NBNS, RADIUS_VENDOR_MICROSOFT,
        RADIUS_VTYPE_MS_SECONDARY_NBNS_SERVER },
    { 0 }
};

int
iked_radius_request(struct iked *env, struct iked_sa *sa,
    struct iked_message *msg)
{
        struct eap_message              *eap;
        RADIUS_PACKET                   *pkt;
        size_t                           len;

        eap = ibuf_data(msg->msg_eapmsg);
        len = betoh16(eap->eap_length);
        if (eap->eap_code != EAP_CODE_RESPONSE) {
                log_debug("%s: eap_code is not response %u", __func__,
                    (unsigned)eap->eap_code);
                return -1;
        }

        if (eap->eap_type == EAP_TYPE_IDENTITY) {
                if ((sa->sa_radreq = calloc(1,
                    sizeof(struct iked_radserver_req))) == NULL) {
                        log_debug(
                            "%s: calloc failed for iked_radserver_req: %s",
                            __func__, strerror(errno));
                        return (-1);
                }
                timer_set(env, &sa->sa_radreq->rr_timer,
                    iked_radius_request_send, sa->sa_radreq);
                sa->sa_radreq->rr_user = strdup(msg->msg_eap.eam_identity);
        }

        if ((pkt = radius_new_request_packet(RADIUS_CODE_ACCESS_REQUEST))
            == NULL) {
                log_debug("%s: radius_new_request_packet failed %s", __func__,
                    strerror(errno));
                return -1;
        }

        radius_put_string_attr(pkt, RADIUS_TYPE_USER_NAME,
            sa->sa_radreq->rr_user);
        if (sa->sa_radreq->rr_state != NULL)
                radius_put_raw_attr(pkt, RADIUS_TYPE_STATE,
                    ibuf_data(sa->sa_radreq->rr_state),
                    ibuf_size(sa->sa_radreq->rr_state));

        if (radius_put_raw_attr_cat(pkt, RADIUS_TYPE_EAP_MESSAGE,
            (uint8_t *)eap, len) == -1) {
                log_debug("%s: radius_put_raw_attr_cat failed %s", __func__,
                    strerror(errno));
                return -1;
        }

        iked_radius_fill_attributes(sa, pkt);

        /* save the request, it'll be needed for message authentication */
        if (sa->sa_radreq->rr_reqpkt != NULL)
                radius_delete_packet(sa->sa_radreq->rr_reqpkt);
        sa->sa_radreq->rr_reqpkt = pkt;
        sa->sa_radreq->rr_sa = sa;
        sa->sa_radreq->rr_ntry = 0;

        iked_radius_request_send(env, sa->sa_radreq);

        return 0;
}

void
iked_radius_request_free(struct iked *env, struct iked_radserver_req *req)
{
        if (req == NULL)
                return;
        timer_del(env, &req->rr_timer);
        free(req->rr_user);
        ibuf_free(req->rr_state);
        if (req->rr_reqpkt)
                radius_delete_packet(req->rr_reqpkt);
        if (req->rr_sa)
                req->rr_sa->sa_radreq = NULL;
        if (req->rr_server)
                TAILQ_REMOVE(&req->rr_server->rs_reqs, req, rr_entry);
        free(req);
}

void
iked_radius_on_event(int fd, short ev, void *ctx)
{
        struct iked                     *env;
        struct iked_radserver           *server = ctx;
        struct iked_radserver_req       *req;
        const struct iked_radcfgmap     *cfgmap;
        RADIUS_PACKET                   *pkt;
        int                              i, resid;
        struct ibuf                     *e;
        const void                      *attrval;
        size_t                           attrlen;
        uint8_t                          code;
        char                             username[256];
        u_char                           eapmsk[128];
        /* RFC 3748 defines the MSK minimum size is 64 bytes */
        size_t                           eapmsksiz = sizeof(eapmsk);

        env = server->rs_env;
        pkt = radius_recv(server->rs_sock, 0);
        if (pkt == NULL) {
                log_info("%s: receiving a RADIUS message failed: %s", __func__,
                    strerror(errno));
                return;
        }
        resid = radius_get_id(pkt);

        TAILQ_FOREACH(req, &server->rs_reqs, rr_entry) {
                if (req->rr_reqid == resid)
                        break;
        }
        if (req == NULL) {
                log_debug("%s: received an unknown RADIUS message: id=%u",
                    __func__, (unsigned)resid);
                radius_delete_packet(pkt);
                return;
        }

        radius_set_request_packet(pkt, req->rr_reqpkt);
        if (radius_check_response_authenticator(pkt, server->rs_secret) != 0) {
                log_info("%s: received an invalid RADIUS message: bad "
                    "response authenticator", __func__);
                radius_delete_packet(pkt);
                return;
        }
        if (req->rr_accounting) {
                /* accounting */
                code = radius_get_code(pkt);
                switch (code) {
                case RADIUS_CODE_ACCOUNTING_RESPONSE: /* Expected */
                        break;
                default:
                        log_info("%s: received an invalid RADIUS message: "
                            "code %u", __func__, (unsigned)code);
                }
                radius_delete_packet(pkt);
                iked_radius_request_free(env, req);
                return;
        }

        /* authentication */
        if (radius_check_message_authenticator(pkt, server->rs_secret) != 0) {
                log_info("%s: received an invalid RADIUS message: bad "
                    "message authenticator", __func__);
                radius_delete_packet(pkt);
                return;
        }

        timer_del(env, &req->rr_timer);
        req->rr_ntry = 0;

        if (req->rr_sa == NULL)
                goto fail;

        code = radius_get_code(pkt);
        switch (code) {
        case RADIUS_CODE_ACCESS_CHALLENGE:
                if (radius_get_raw_attr_ptr(pkt, RADIUS_TYPE_STATE, &attrval,
                    &attrlen) != 0) {
                        log_info("%s: received an invalid RADIUS message: no "
                            "state attribute", __func__);
                        goto fail;
                }
                if (req->rr_state != NULL &&
                    ibuf_set(req->rr_state, 0, attrval, attrlen) != 0) {
                        ibuf_free(req->rr_state);
                        req->rr_state = NULL;
                }
                if (req->rr_state == NULL &&
                    (req->rr_state = ibuf_new(attrval, attrlen)) == NULL) {
                        log_info("%s: ibuf_new() failed: %s", __func__,
                            strerror(errno));
                        goto fail;
                }
                break;
        case RADIUS_CODE_ACCESS_ACCEPT:
                log_info("%s: received Access-Accept for %s",
                    SPI_SA(req->rr_sa, __func__), req->rr_user);
                /* Try to retrieve the EAP MSK from the RADIUS response */
                if (radius_get_eap_msk(pkt, eapmsk, &eapmsksiz,
                    server->rs_secret) == 0) {
                        ibuf_free(req->rr_sa->sa_eapmsk);
                        if ((req->rr_sa->sa_eapmsk = ibuf_new(eapmsk,
                            eapmsksiz)) == NULL) {
                                log_info("%s: ibuf_new() failed: %s", __func__,
                                    strerror(errno));
                                goto fail;
                        }
                } else
                        log_debug("Could not retrieve the EAP MSK from the "
                            "RADIUS message");

                free(req->rr_sa->sa_eapid);
                /* The EAP identity might be protected (RFC 3748 7.3) */
                if (radius_get_string_attr(pkt, RADIUS_TYPE_USER_NAME,
                    username, sizeof(username)) == 0 &&
                    strcmp(username, req->rr_user) != 0) {
                        /*
                         * The Access-Accept might have a User-Name.  It
                         * should be used for Accounting (RFC 2865 5.1).
                         */
                        free(req->rr_user);
                        req->rr_sa->sa_eapid = strdup(username);
                } else
                        req->rr_sa->sa_eapid = req->rr_user;
                req->rr_user = NULL;

                if (radius_get_raw_attr_ptr(pkt, RADIUS_TYPE_CLASS, &attrval,
                    &attrlen) == 0) {
                        ibuf_free(req->rr_sa->sa_eapclass);
                        if ((req->rr_sa->sa_eapclass = ibuf_new(attrval,
                            attrlen)) == NULL) {
                                log_info("%s: ibuf_new() failed: %s", __func__,
                                    strerror(errno));
                        }
                }

                sa_state(env, req->rr_sa, IKEV2_STATE_AUTH_SUCCESS);

                /* Map RADIUS attributes to cp */
                if (TAILQ_EMPTY(&env->sc_radcfgmaps)) {
                        for (i = 0; radius_cfgmaps[i].cfg_type != 0; i++) {
                                cfgmap = &radius_cfgmaps[i];
                                iked_radius_config(req, pkt, cfgmap->cfg_type,
                                    cfgmap->vendor_id, cfgmap->attr_type);
                        }
                } else {
                        TAILQ_FOREACH(cfgmap, &env->sc_radcfgmaps, entry)
                                iked_radius_config(req, pkt, cfgmap->cfg_type,
                                    cfgmap->vendor_id, cfgmap->attr_type);
                }

                TAILQ_REMOVE(&server->rs_reqs, req, rr_entry);
                req->rr_server = NULL;
                break;
        case RADIUS_CODE_ACCESS_REJECT:
                log_info("%s: received Access-Reject for %s",
                    SPI_SA(req->rr_sa, __func__), req->rr_user);
                TAILQ_REMOVE(&server->rs_reqs, req, rr_entry);
                req->rr_server = NULL;
                break;
        default:
                log_debug("%s: received an invalid RADIUS message: code %u",
                    __func__, (unsigned)code);
                break;
        }

        /* get the length first */
        if (radius_get_raw_attr_cat(pkt, RADIUS_TYPE_EAP_MESSAGE, NULL,
            &attrlen) != 0) {
                log_info("%s: failed to retrieve the EAP message", __func__);
                goto fail;
        }
        /* allocate a buffer */
        if ((e = ibuf_new(NULL, attrlen)) == NULL) {
                log_info("%s: ibuf_new() failed: %s", __func__,
                    strerror(errno));
                goto fail;
        }
        /* copy the message to the buffer */
        if (radius_get_raw_attr_cat(pkt, RADIUS_TYPE_EAP_MESSAGE,
            ibuf_data(e), &attrlen) != 0) {
                ibuf_free(e);
                log_info("%s: failed to retrieve the EAP message", __func__);
                goto fail;
        }
        radius_delete_packet(pkt);
        ikev2_send_ike_e(env, req->rr_sa, e, IKEV2_PAYLOAD_EAP,
            IKEV2_EXCHANGE_IKE_AUTH, 1);
        ibuf_free(e);
        /* keep request for challenge state and config parameters */
        req->rr_reqid = -1;     /* release reqid */
        return;
 fail:
        radius_delete_packet(pkt);
        if (req->rr_server != NULL)
                TAILQ_REMOVE(&server->rs_reqs, req, rr_entry);
        req->rr_server = NULL;
        if (req->rr_sa != NULL) {
                ikev2_ike_sa_setreason(req->rr_sa, "RADIUS request failed");
                sa_free(env, req->rr_sa);
        }
}

void
iked_radius_request_send(struct iked *env, void *ctx)
{
        struct iked_radserver_req       *req = ctx, *req0;
        struct iked_radserver           *server = req->rr_server;
        const int                        timeouts[] = { 2, 4, 8 };
        uint8_t                          seq;
        int                              i, max_tries, max_failovers;
        struct sockaddr_storage          ss;
        socklen_t                        sslen;
        struct iked_radservers          *radservers;
        struct timespec                  now;

        if (!req->rr_accounting) {
                max_tries = env->sc_radauth.max_tries;
                max_failovers = env->sc_radauth.max_failovers;
                radservers = &env->sc_radauthservers;
        } else {
                max_tries = env->sc_radacct.max_tries;
                max_failovers = env->sc_radacct.max_failovers;
                radservers = &env->sc_radacctservers;
        }

        if (req->rr_ntry > max_tries) {
                req->rr_ntry = 0;
                log_info("%s: RADIUS server %s failed", __func__,
                    print_addr(&server->rs_sockaddr));
 next_server:
                TAILQ_REMOVE(&server->rs_reqs, req, rr_entry);
                req->rr_server = NULL;
                if (req->rr_nfailover >= max_failovers ||
                    TAILQ_NEXT(server, rs_entry) == NULL) {
                        log_info("%s: No more RADIUS server", __func__);
                        goto fail;
                } else if (req->rr_state != NULL) {
                        log_info("%s: Can't change RADIUS server: "
                            "client has a state already", __func__);
                        goto fail;
                } else {
                        TAILQ_REMOVE(radservers, server, rs_entry);
                        TAILQ_INSERT_TAIL(radservers, server, rs_entry);
                        server = TAILQ_FIRST(radservers);
                        log_info("%s: RADIUS server %s is active",
                            __func__, print_addr(&server->rs_sockaddr));
                }
                req->rr_nfailover++;
        }

        if (req->rr_server != NULL &&
            req->rr_server != TAILQ_FIRST(radservers)) {
                /* Current server is marked fail */
                if (req->rr_state != NULL || req->rr_nfailover >= max_failovers)
                        goto fail; /* can't fail over */
                TAILQ_REMOVE(&server->rs_reqs, req, rr_entry);
                req->rr_server = NULL;
                req->rr_nfailover++;
        }

        if (req->rr_server == NULL) {
                /* Select a new server */
                server = TAILQ_FIRST(radservers);
                if (server == NULL) {
                        log_info("%s: No RADIUS server is configured",
                            __func__);
                        goto fail;
                }
                TAILQ_INSERT_TAIL(&server->rs_reqs, req, rr_entry);
                req->rr_server = server;

                /* Prepare NAS-IP-Address */
                if (server->rs_nas_ipv4.s_addr == INADDR_ANY &&
                    IN6_IS_ADDR_UNSPECIFIED(&server->rs_nas_ipv6)) {
                        sslen = sizeof(ss);
                        if (getsockname(server->rs_sock, (struct sockaddr *)&ss,
                            &sslen) == 0) {
                                if (ss.ss_family == AF_INET)
                                        server->rs_nas_ipv4 =
                                            ((struct sockaddr_in *)&ss)
                                            ->sin_addr;
                                else
                                        server->rs_nas_ipv6 =
                                            ((struct sockaddr_in6 *)&ss)
                                            ->sin6_addr;
                        }
                }
        }
        if (req->rr_ntry == 0) {
                /* decide the ID */
                seq = ++server->rs_reqseq;
                for (i = 0; i <= UCHAR_MAX; i++) {
                        TAILQ_FOREACH(req0, &server->rs_reqs, rr_entry) {
                                if (req0->rr_reqid == -1)
                                        continue;
                                if (req0->rr_reqid == seq)
                                        break;
                        }
                        if (req0 == NULL)
                                break;
                        seq++;
                }
                if (i > UCHAR_MAX) {
                        log_info("%s: RADIUS server %s failed.  Too many "
                            "pending requests", __func__,
                            print_addr(&server->rs_sockaddr));
                        if (TAILQ_NEXT(server, rs_entry) != NULL)
                                goto next_server;
                        goto fail;
                }
                req->rr_reqid = seq;
                radius_set_id(req->rr_reqpkt, req->rr_reqid);
        }

        if (server->rs_nas_ipv4.s_addr != INADDR_ANY)
                radius_put_ipv4_attr(req->rr_reqpkt, RADIUS_TYPE_NAS_IP_ADDRESS,
                    server->rs_nas_ipv4);
        else if (!IN6_IS_ADDR_UNSPECIFIED(&server->rs_nas_ipv6))
                radius_put_ipv6_attr(req->rr_reqpkt,
                    RADIUS_TYPE_NAS_IPV6_ADDRESS, &server->rs_nas_ipv6);
        /* Identifier */
        radius_put_string_attr(req->rr_reqpkt, RADIUS_TYPE_NAS_IDENTIFIER,
            IKED_NAS_ID);

        if (req->rr_accounting) {
                if (req->rr_ntry == 0 && req->rr_nfailover == 0)
                        radius_put_uint32_attr(req->rr_reqpkt,
                            RADIUS_TYPE_ACCT_DELAY_TIME, 0);
                else {
                        clock_gettime(CLOCK_MONOTONIC, &now);
                        timespecsub(&now, &req->rr_accttime, &now);
                        radius_put_uint32_attr(req->rr_reqpkt,
                            RADIUS_TYPE_ACCT_DELAY_TIME, now.tv_sec);
                }
                radius_set_accounting_request_authenticator(req->rr_reqpkt,
                    server->rs_secret);
        } else {
                radius_put_message_authenticator(req->rr_reqpkt,
                    server->rs_secret);
        }

        if (radius_send(server->rs_sock, req->rr_reqpkt, 0) < 0)
                log_info("%s: sending a RADIUS message failed: %s", __func__,
                    strerror(errno));

        if (req->rr_ntry >= (int)nitems(timeouts))
                timer_add(env, &req->rr_timer, timeouts[nitems(timeouts) - 1]);
        else
                timer_add(env, &req->rr_timer, timeouts[req->rr_ntry]);
        req->rr_ntry++;
        return;
 fail:
        if (req->rr_server != NULL)
                TAILQ_REMOVE(&server->rs_reqs, req, rr_entry);
        req->rr_server = NULL;
        if (req->rr_sa != NULL) {
                ikev2_ike_sa_setreason(req->rr_sa, "RADIUS request failed");
                sa_free(env, req->rr_sa);
        }
}

void
iked_radius_fill_attributes(struct iked_sa *sa, RADIUS_PACKET *pkt)
{
        char    port_id[16 + 1];

        /* NAS Port Type = Virtual */
        radius_put_uint32_attr(pkt,
            RADIUS_TYPE_NAS_PORT_TYPE, RADIUS_NAS_PORT_TYPE_VIRTUAL);
        /* Service Type =  Framed */
        radius_put_uint32_attr(pkt, RADIUS_TYPE_SERVICE_TYPE,
            RADIUS_SERVICE_TYPE_FRAMED);
        /* Tunnel Type = EAP */
        radius_put_uint32_attr(pkt, RADIUS_TYPE_TUNNEL_TYPE,
            RADIUS_TUNNEL_TYPE_ESP);
        /* NAS-Port-ID = ISPI */
        snprintf(port_id, sizeof(port_id), "%016llx",
            (unsigned long long)sa->sa_hdr.sh_ispi);
        radius_put_string_attr(pkt, RADIUS_TYPE_NAS_PORT_ID, port_id);

        radius_put_string_attr(pkt, RADIUS_TYPE_CALLED_STATION_ID,
            print_addr(&sa->sa_local.addr));
        radius_put_string_attr(pkt, RADIUS_TYPE_CALLING_STATION_ID,
            print_addr(&sa->sa_peer.addr));
}

void
iked_radius_config(struct iked_radserver_req *req, const RADIUS_PACKET *pkt,
    int cfg_type, uint32_t vendor_id, uint8_t attr_type)
{
        unsigned int             i;
        struct iked_sa          *sa = req->rr_sa;
        struct in_addr           ia4;
        struct in6_addr          ia6;
        struct sockaddr_in      *sin4;
        struct sockaddr_in6     *sin6;
        struct iked_addr        *addr;
        struct iked_cfg         *ikecfg;

        for (i = 0; i < sa->sa_policy->pol_ncfg; i++) {
                ikecfg = &sa->sa_policy->pol_cfg[i];
                if (ikecfg->cfg_type == cfg_type &&
                    ikecfg->cfg_type != IKEV2_CFG_INTERNAL_IP4_ADDRESS)
                        return; /* use config rather than radius */
        }
        switch (cfg_type) {
        case IKEV2_CFG_INTERNAL_IP4_ADDRESS:
        case IKEV2_CFG_INTERNAL_IP4_NETMASK:
        case IKEV2_CFG_INTERNAL_IP4_DNS:
        case IKEV2_CFG_INTERNAL_IP4_NBNS:
        case IKEV2_CFG_INTERNAL_IP4_DHCP:
        case IKEV2_CFG_INTERNAL_IP4_SERVER:
                if (vendor_id == 0 && radius_has_attr(pkt, attr_type))
                        radius_get_ipv4_attr(pkt, attr_type, &ia4);
                else if (vendor_id != 0 && radius_has_vs_attr(pkt, vendor_id,
                    attr_type))
                        radius_get_vs_ipv4_attr(pkt, vendor_id, attr_type,
                            &ia4);
                else
                        break; /* no attribute contained */

                if (cfg_type == IKEV2_CFG_INTERNAL_IP4_NETMASK) {
                        /*
                         * This assumes IKEV2_CFG_INTERNAL_IP4_ADDRESS is
                         * called before IKEV2_CFG_INTERNAL_IP4_NETMASK
                         */
                        if (sa->sa_rad_addr == NULL) {
                                /*
                                 * RFC 7296, IKEV2_CFG_INTERNAL_IP4_NETMASK
                                 * must be used with
                                 * IKEV2_CFG_INTERNAL_IP4_ADDRESS
                                 */
                                break;
                        }
                        if (ia4.s_addr == 0) {
                                log_debug("%s: netmask is wrong", __func__);
                                break;
                        }
                        if (ia4.s_addr == htonl(0))
                                sa->sa_rad_addr->addr_mask = 0;
                        else
                                sa->sa_rad_addr->addr_mask =
                                    33 - ffs(ntohl(ia4.s_addr));
                        if (sa->sa_rad_addr->addr_mask < 32)
                                sa->sa_rad_addr->addr_net = 1;
                }
                if (cfg_type == IKEV2_CFG_INTERNAL_IP4_ADDRESS) {
                        if ((addr = calloc(1, sizeof(*addr))) == NULL) {
                                log_warn("%s: calloc", __func__);
                                return;
                        }
                        sa->sa_rad_addr = addr;
                } else {
                        req->rr_cfg[req->rr_ncfg].cfg_action = IKEV2_CP_REPLY;
                        req->rr_cfg[req->rr_ncfg].cfg_type = cfg_type;
                        addr = &req->rr_cfg[req->rr_ncfg].cfg.address;
                        req->rr_ncfg++;
                }
                addr->addr_af = AF_INET;
                sin4 = (struct sockaddr_in *)&addr->addr;
                sin4->sin_family = AF_INET;
                sin4->sin_len = sizeof(struct sockaddr_in);
                sin4->sin_addr = ia4;
                break;
        case IKEV2_CFG_INTERNAL_IP6_ADDRESS:
        case IKEV2_CFG_INTERNAL_IP6_DNS:
        case IKEV2_CFG_INTERNAL_IP6_NBNS:
        case IKEV2_CFG_INTERNAL_IP6_DHCP:
        case IKEV2_CFG_INTERNAL_IP6_SERVER:
                if (vendor_id == 0 && radius_has_attr(pkt, attr_type))
                        radius_get_ipv6_attr(pkt, attr_type, &ia6);
                else if (vendor_id != 0 && radius_has_vs_attr(pkt, vendor_id,
                    attr_type))
                        radius_get_vs_ipv6_attr(pkt, vendor_id, attr_type,
                            &ia6);
                else
                        break; /* no attribute contained */

                if (cfg_type == IKEV2_CFG_INTERNAL_IP6_ADDRESS) {
                        if ((addr = calloc(1, sizeof(*addr))) == NULL) {
                                log_warn("%s: calloc", __func__);
                                return;
                        }
                        sa->sa_rad_addr = addr;
                } else {
                        req->rr_cfg[req->rr_ncfg].cfg_action = IKEV2_CP_REPLY;
                        req->rr_cfg[req->rr_ncfg].cfg_type = cfg_type;
                        addr = &req->rr_cfg[req->rr_ncfg].cfg.address;
                        req->rr_ncfg++;
                }
                addr->addr_af = AF_INET;
                sin6 = (struct sockaddr_in6 *)&addr->addr;
                sin6->sin6_family = AF_INET6;
                sin6->sin6_len = sizeof(struct sockaddr_in6);
                sin6->sin6_addr = ia6;
                break;
        }
        return;
}

void
iked_radius_acct_on(struct iked *env)
{
        if (TAILQ_EMPTY(&env->sc_radacctservers))
                return;
        if (env->sc_radaccton == 0) {   /* trigger once */
                iked_radius_acct_request(env, NULL,
                    RADIUS_ACCT_STATUS_TYPE_ACCT_ON);
                env->sc_radaccton = 1;
        }
}

void
iked_radius_acct_off(struct iked *env)
{
        iked_radius_acct_request(env, NULL, RADIUS_ACCT_STATUS_TYPE_ACCT_OFF);
}

void
iked_radius_acct_start(struct iked *env, struct iked_sa *sa)
{
        iked_radius_acct_request(env, sa, RADIUS_ACCT_STATUS_TYPE_START);
}

void
iked_radius_acct_stop(struct iked *env, struct iked_sa *sa)
{
        iked_radius_acct_request(env, sa, RADIUS_ACCT_STATUS_TYPE_STOP);
}

void
iked_radius_acct_request(struct iked *env, struct iked_sa *sa, uint8_t stype)
{
        struct iked_radserver_req       *req;
        RADIUS_PACKET                   *pkt;
        struct iked_addr                *addr4 = NULL;
        struct iked_addr                *addr6 = NULL;
        struct in_addr                   mask4;
        char                             sa_id[IKED_ID_SIZE];
        char                             sid[16 + 1];
        struct timespec                  now;
        int                              cause;

        if (TAILQ_EMPTY(&env->sc_radacctservers))
                return;
        /*
         * In RFC2866 5.6, "Users who are delivered service without
         * being authenticated SHOULD NOT generate Accounting records
         */
        if (sa != NULL && sa->sa_eapid == NULL) {
                /* fallback to IKEID for accounting */
                if (ikev2_print_id(IKESA_DSTID(sa), sa_id, sizeof(sa_id)) != -1)
                        sa->sa_eapid = strdup(sa_id);
                if (sa->sa_eapid == NULL)
                        return;
        }

        if ((req = calloc(1, sizeof(struct iked_radserver_req))) == NULL) {
                log_debug("%s: calloc faile for iked_radserver_req: %s",
                    __func__, strerror(errno));
                return;
        }
        req->rr_accounting = 1;
        clock_gettime(CLOCK_MONOTONIC, &now);
        req->rr_accttime = now;
        timer_set(env, &req->rr_timer, iked_radius_request_send, req);

        if ((pkt = radius_new_request_packet(RADIUS_CODE_ACCOUNTING_REQUEST))
            == NULL) {
                log_debug("%s: radius_new_request_packet failed %s", __func__,
                    strerror(errno));
                return;
        }

        /* RFC 2866  5.1. Acct-Status-Type */
        radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_STATUS_TYPE, stype);

        if (sa == NULL) {
                /* ASSERT(stype == RADIUS_ACCT_STATUS_TYPE_ACCT_ON ||
                    stype == RADIUS_ACCT_STATUS_TYPE_ACCT_OFF) */
                req->rr_reqpkt = pkt;
                req->rr_ntry = 0;
                iked_radius_request_send(env, req);
                return;
        }

        iked_radius_fill_attributes(sa, pkt);

        radius_put_string_attr(pkt, RADIUS_TYPE_USER_NAME, sa->sa_eapid);

        /* RFC 2866  5.5. Acct-Session-Id */
        snprintf(sid, sizeof(sid), "%016llx",
            (unsigned long long)sa->sa_hdr.sh_ispi);
        radius_put_string_attr(pkt, RADIUS_TYPE_ACCT_SESSION_ID, sid);

        /* Accounting Request must have Framed-IP-Address */
        addr4 = sa->sa_addrpool;
        if (addr4 != NULL) {
                radius_put_ipv4_attr(pkt, RADIUS_TYPE_FRAMED_IP_ADDRESS,
                    ((struct sockaddr_in *)&addr4->addr)->sin_addr);
                if (addr4->addr_mask != 0) {
                        mask4.s_addr = htonl(
                            0xFFFFFFFFUL << (32 - addr4->addr_mask));
                        radius_put_ipv4_attr(pkt,
                            RADIUS_TYPE_FRAMED_IP_NETMASK, mask4);
                }
        }
        addr6 = sa->sa_addrpool6;
        if (addr6 != NULL)
                radius_put_ipv6_attr(pkt, RADIUS_TYPE_FRAMED_IPV6_ADDRESS,
                    &((struct sockaddr_in6 *)&addr6->addr)->sin6_addr);

        /* RFC2866 5.6 Acct-Authentic */
        radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_AUTHENTIC,
            (sa->sa_radreq != NULL)? RADIUS_ACCT_AUTHENTIC_RADIUS :
            RADIUS_ACCT_AUTHENTIC_LOCAL);

        switch (stype) {
        case RADIUS_ACCT_STATUS_TYPE_START:
                if (req->rr_sa && req->rr_sa->sa_eapclass != NULL)
                        radius_put_raw_attr(pkt, RADIUS_TYPE_CLASS,
                            ibuf_data(req->rr_sa->sa_eapclass),
                            ibuf_size(req->rr_sa->sa_eapclass));
                break;
        case RADIUS_ACCT_STATUS_TYPE_INTERIM_UPDATE:
        case RADIUS_ACCT_STATUS_TYPE_STOP:
                /* RFC 2866 5.7.  Acct-Session-Time */
                timespecsub(&now, &sa->sa_starttime, &now);
                radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_SESSION_TIME,
                    now.tv_sec);
                /* RFC 2866 5.10 Acct-Terminate-Cause */
                cause = RADIUS_TERMNATE_CAUSE_SERVICE_UNAVAIL;
                if (sa->sa_reason) {
                        if (strcmp(sa->sa_reason, "received delete") == 0) {
                                cause = RADIUS_TERMNATE_CAUSE_USER_REQUEST;
                        } else if (strcmp(sa->sa_reason, "SA rekeyed") == 0) {
                                cause = RADIUS_TERMNATE_CAUSE_SESSION_TIMEOUT;
                        } else if (strncmp(sa->sa_reason, "retransmit",
                            strlen("retransmit")) == 0) {
                                cause = RADIUS_TERMNATE_CAUSE_LOST_SERVICE;
                        } else if (strcmp(sa->sa_reason,
                            "disconnect requested") == 0) {
                                cause = RADIUS_TERMNATE_CAUSE_ADMIN_RESET;
                        }
                }
                radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_TERMINATE_CAUSE,
                    cause);
                /* I/O statistics {Input,Output}-{Packets,Octets,Gigawords} */
                radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_INPUT_PACKETS,
                    sa->sa_stats.sas_ipackets);
                radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_OUTPUT_PACKETS,
                    sa->sa_stats.sas_opackets);
                radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_INPUT_OCTETS,
                    sa->sa_stats.sas_ibytes & 0xffffffffUL);
                radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_OUTPUT_OCTETS,
                    sa->sa_stats.sas_obytes & 0xffffffffUL);
                radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_INPUT_GIGAWORDS,
                    sa->sa_stats.sas_ibytes >> 32);
                radius_put_uint32_attr(pkt, RADIUS_TYPE_ACCT_OUTPUT_GIGAWORDS,
                    sa->sa_stats.sas_obytes >> 32);
                break;
        }
        req->rr_reqpkt = pkt;
        req->rr_ntry = 0;
        iked_radius_request_send(env, req);
}

void
iked_radius_dae_on_event(int fd, short ev, void *ctx)
{
        struct iked_raddae      *dae = ctx;
        struct iked             *env = dae->rd_env;
        RADIUS_PACKET           *req = NULL, *res = NULL;
        struct sockaddr_storage  ss;
        socklen_t                sslen;
        struct iked_radclient   *client;
        struct iked_sa          *sa = NULL;
        char                     attr[256], username[256];
        char                    *endp, *reason, *nakcause = NULL;
        int                      code, n = 0;
        uint64_t                 ispi = 0;
        uint32_t                 u32, cause = 0;
        struct iked_addr        *addr4 = NULL;

        reason = "disconnect requested";

        sslen = sizeof(ss);
        req = radius_recvfrom(dae->rd_sock, 0, (struct sockaddr *)&ss, &sslen);
        if (req == NULL) {
                log_warn("%s: receiving a RADIUS message failed: %s", __func__,
                    strerror(errno));
                return;
        }
        TAILQ_FOREACH(client, &env->sc_raddaeclients, rc_entry) {
                if (sockaddr_cmp((struct sockaddr *)&client->rc_sockaddr,
                    (struct sockaddr *)&ss, -1) == 0)
                        break;
        }
        if (client == NULL) {
                log_warnx("%s: received RADIUS message from %s: "
                    "unknown client", __func__, print_addr(&ss));
                goto out;
        }

        if (radius_check_accounting_request_authenticator(req,
            client->rc_secret) != 0) {
                log_warnx("%s: received an invalid RADIUS message from %s: bad "
                    "response authenticator", __func__, print_addr(&ss));
                goto out;
        }

        if ((code = radius_get_code(req)) != RADIUS_CODE_DISCONNECT_REQUEST) {
                /* Code other than Disconnect-Request is not supported */
                if (code == RADIUS_CODE_COA_REQUEST) {
                        code = RADIUS_CODE_COA_NAK;
                        cause = RADIUS_ERROR_CAUSE_ADMINISTRATIVELY_PROHIBITED;
                        nakcause = "Coa-Request is not supported";
                        goto send;
                }
                log_warnx("%s: received an invalid RADIUS message "
                    "from %s: unknown code %d", __func__,
                    print_addr(&ss), code);
                goto out;
        }

        log_info("received Disconnect-Request from %s", print_addr(&ss));

        if (radius_get_string_attr(req, RADIUS_TYPE_NAS_IDENTIFIER, attr,
            sizeof(attr)) == 0 && strcmp(attr, IKED_NAS_ID) != 0) {
                cause = RADIUS_ERROR_CAUSE_NAS_IDENTIFICATION_MISMATCH;
                nakcause = "NAS-Identifier is not matched";
                goto search_done;
        }

        /* prepare User-Name attribute */
        memset(username, 0, sizeof(username));
        radius_get_string_attr(req, RADIUS_TYPE_USER_NAME, username,
            sizeof(username));

        if (radius_get_string_attr(req, RADIUS_TYPE_ACCT_SESSION_ID, attr,
            sizeof(attr)) == 0) {
                /* the client is to disconnect a session */
                ispi = strtoull(attr, &endp, 16);
                if (attr[0] == '\0' || *endp != '\0' || errno == ERANGE ||
                    ispi == ULLONG_MAX) {
                        cause = RADIUS_ERROR_CAUSE_INVALID_ATTRIBUTE_VALUE;
                        nakcause = "Session-Id is wrong";
                        goto search_done;

                }
                RB_FOREACH(sa, iked_sas, &env->sc_sas) {
                        if (sa->sa_hdr.sh_ispi == ispi)
                                break;
                }
                if (sa == NULL)
                        goto search_done;
                if (username[0] != '\0' && (sa->sa_eapid == NULL ||
                    strcmp(username, sa->sa_eapid) != 0)) {
                        /* specified User-Name attribute is mismatched */
                        cause = RADIUS_ERROR_CAUSE_INVALID_ATTRIBUTE_VALUE;
                        nakcause = "User-Name is not matched";
                        goto search_done;
                }
                ikev2_ike_sa_setreason(sa, reason);
                ikev2_ike_sa_delete(env, sa);
                n++;
        } else if (username[0] != '\0') {
                RB_FOREACH(sa, iked_sas, &env->sc_sas) {
                        if (sa->sa_eapid != NULL &&
                            strcmp(sa->sa_eapid, username) == 0) {
                                ikev2_ike_sa_setreason(sa, reason);
                                ikev2_ike_sa_delete(env, sa);
                                n++;
                        }
                }
        } else if (radius_get_uint32_attr(req, RADIUS_TYPE_FRAMED_IP_ADDRESS,
            &u32) == 0) {
                RB_FOREACH(sa, iked_sas, &env->sc_sas) {
                        addr4 = sa->sa_addrpool;
                        if (addr4 != NULL) {
                                if (u32 == ((struct sockaddr_in *)&addr4->addr)
                                    ->sin_addr.s_addr) {
                                        ikev2_ike_sa_setreason(sa, reason);
                                        ikev2_ike_sa_delete(env, sa);
                                        n++;
                                }
                        }
                }
        }
 search_done:
        if (n > 0)
                code = RADIUS_CODE_DISCONNECT_ACK;
        else {
                if (nakcause == NULL)
                        nakcause = "session not found";
                if (cause == 0)
                        cause = RADIUS_ERROR_CAUSE_SESSION_NOT_FOUND;
                code = RADIUS_CODE_DISCONNECT_NAK;
        }
 send:
        res = radius_new_response_packet(code, req);
        if (res == NULL) {
                log_warn("%s: radius_new_response_packet", __func__);
                goto out;
        }
        if (cause != 0)
                radius_put_uint32_attr(res, RADIUS_TYPE_ERROR_CAUSE, cause);
        radius_set_response_authenticator(res, client->rc_secret);
        if (radius_sendto(dae->rd_sock, res, 0, (struct sockaddr *)&ss, sslen)
            == -1)
                log_warn("%s: sendto", __func__);
        log_info("send %s for %s%s%s",
            (code == RADIUS_CODE_DISCONNECT_ACK)? "Disconnect-ACK" :
            (code == RADIUS_CODE_DISCONNECT_NAK)? "Disconnect-NAK" : "CoA-NAK",
            print_addr(&ss), (nakcause)? ": " : "", (nakcause)? nakcause : "");
 out:
        radius_delete_packet(req);
        if (res != NULL)
                radius_delete_packet(res);
}