/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */
/*
 * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
 */
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

/*
 * This is an implementation of RCPBIND according the RFC 1833: Binding
 * Protocols for ONC RPC Version 2.  The RFC specifies three versions of the
 * binding protocol:
 *
 * 1) RPCBIND Version 3 (Section 2.2.1 of the RFC)
 * 2) RPCBIND, Version 4 (Section 2.2.2 of the RFC)
 * 3) Port Mapper Program Protocol (Section 3 of the RFC)
 *
 * Where the "Port Mapper Program Protocol" is refered as Version 2 of the
 * binding protocol.  The implementation of the Version 2 of the binding
 * protocol is compiled in only in a case the PORTMAP macro is defined (by
 * default it is defined).
 *
 * The implementation is based on top of the networking services library -
 * libnsl(3lib) and uses Automatic MT mode (see rpc_control(3nsl) and
 * svc_run(3nsl) for more details).
 *
 * Usually, when a thread handles an RPCBIND procedure (one that arrived from a
 * client), it obtains the data for the response internally, and immediately
 * sends the response back to the client.  The only exception to this rule are
 * remote (aka indirect) RPC calls, for example RPCBPROC_INDIRECT.  Such
 * procedures are designed to forward the RPC request from the client to some
 * other RPC service specified by the client, wait for the result, and forward
 * the result back to the client.  This is implemented in rpcbproc_callit_com().
 *
 * The response from the other (remote) RPC service is handled in
 * handle_reply(), where the thread waiting in rpcbproc_callit_com() is woken
 * up to finish the handling and to send (forward) the response back to the
 * client.
 *
 * The thread implementing the indirect RPC call might be blocked in the
 * rpcbproc_callit_com() waiting for the response from the other RPC service
 * for very long time.  During this time the thread is unable to handle other
 * RPCBIND requests.  To avoid a case when all threads are waiting in
 * rpcbproc_callit_com() and there is no free thread able to handle other
 * RPCBIND requests, the implementation has reserved eight threads to never be
 * used for the remote RPC calls.  The number of active remote RPC calls is in
 * rpcb_rmtcalls, the upper limit of such calls is in rpcb_rmtcalls_max.
 *
 * In addition to the worker threads described above, there are two other
 * threads.  The logthread() thread is responsible for asynchronous logging to
 * syslog.  The terminate() thread is signal handler responsible for reload of
 * the rpcbind configuration (on SIGHUP), or for gracefully shutting down
 * rpcbind (otherwise).
 *
 * There are two global lists used for holding the information about the
 * registered services: list_rbl is for Version 3 and 4 of the binding
 * protocol, and list_pml is for Version 2.  To protect these lists, two global
 * readers/writer locks are defined and heavily used across the rpcbind
 * implementation: list_rbl_lock protecting list_rbl, and list_pml_lock,
 * protecting list_pml.
 *
 * The defined locking order is: list_rbl_lock first, list_pml_lock second.
 */

#include <dlfcn.h>
#include <stdio.h>
#include <stdio_ext.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <rpc/rpc.h>
#include <netconfig.h>
#include <netdir.h>
#include <errno.h>
#include <sys/wait.h>
#include <signal.h>
#include <string.h>
#include <stdlib.h>
#include <thread.h>
#include <synch.h>
#include <stdarg.h>
#ifdef PORTMAP
#include <netinet/in.h>
#endif
#include <arpa/inet.h>
#include <sys/termios.h>
#include "rpcbind.h"
#include <sys/syslog.h>
#include <sys/stat.h>
#include <syslog.h>
#include <string.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <rpcsvc/daemon_utils.h>
#include <priv_utils.h>
#include <libscf.h>
#include <sys/ccompile.h>
#include <zone.h>
#include <ctype.h>
#include <limits.h>
#include <assert.h>

static sigset_t sigwaitset;

static void terminate(void);
static void detachfromtty(void);
static void parseargs(int, char *[]);
static void rbllist_add(ulong_t, ulong_t, struct netconfig *, struct netbuf *);
static int init_transport(struct netconfig *);
static int check_netconfig(void);

static boolean_t check_hostserv(struct netconfig *, const char *, const char *);
static int setopt_reuseaddr(int);
static int setopt_anon_mlp(int);
static int setup_callit(int);

static void rpcb_check_init(void);

/* Global variables */
int debugging = 0;      /* Tell me what's going on */
static int ipv6flag = 0;
int doabort = 0;        /* When debugging, do an abort on errors */
static int listen_backlog;
static const int reserved_threads = 8;

/*
 * list_rbl_lock protects list_rbl
 * lock order: list_rbl_lock, list_pml_lock
 */
rwlock_t list_rbl_lock = DEFAULTRWLOCK;
rpcblist_ptr list_rbl;  /* A list of version 3/4 rpcbind services */

char *loopback_dg;      /* Datagram loopback transport, for set and unset */
char *loopback_vc;      /* COTS loopback transport, for set and unset */
char *loopback_vc_ord;  /* COTS_ORD loopback transport, for set and unset */

volatile boolean_t verboselog = B_FALSE;
volatile boolean_t wrap_enabled = B_FALSE;
volatile boolean_t allow_indirect = B_TRUE;
volatile boolean_t local_only = B_TRUE;

/* Local Variable */
static int warmstart = 0;       /* Grab a old copy of registrations */

#ifdef PORTMAP
/*
 * list_pml_lock protects list_pml
 * lock order: list_rbl_lock, list_pml_lock
 */
rwlock_t list_pml_lock = DEFAULTRWLOCK;
PMAPLIST *list_pml;     /* A list of version 2 rpcbind services */

char *udptrans;         /* Name of UDP transport */
char *tcptrans;         /* Name of TCP transport */
char *udp_uaddr;        /* Universal UDP address */
char *tcp_uaddr;        /* Universal TCP address */
#endif
static char servname[] = "rpcbind";
static char superuser[] = "superuser";

static const char daemon_dir[] = DAEMON_DIR;

static void
block_signals(void)
{
        (void) sigemptyset(&sigwaitset);
        (void) sigaddset(&sigwaitset, SIGINT);
        (void) sigaddset(&sigwaitset, SIGTERM);
        (void) sigaddset(&sigwaitset, SIGQUIT);
        (void) sigaddset(&sigwaitset, SIGHUP);
        (void) sigprocmask(SIG_BLOCK, &sigwaitset, NULL);

        /* ignore other signals that could get sent */
        (void) signal(SIGUSR1, SIG_IGN);
        (void) signal(SIGUSR2, SIG_IGN);
}

int
main(int argc, char *argv[])
{
        struct netconfig *nconf;
        void *nc_handle;        /* Net config handle */
        struct rlimit rl;
        int rpc_svc_fdunlim = 1;
        int rpc_svc_mode = RPC_SVC_MT_AUTO;
        int maxrecsz = RPC_MAXDATASIZE;
        boolean_t can_do_mlp;

        block_signals();

        parseargs(argc, argv);

        if (getrlimit(RLIMIT_NOFILE, &rl) != 0) {
                syslog(LOG_ERR, "getrlimit failed");
        } else {
                rl.rlim_cur = rl.rlim_max;
                if (setrlimit(RLIMIT_NOFILE, &rl) != 0)
                        syslog(LOG_ERR, "setrlimit failed");
        }
        (void) enable_extended_FILE_stdio(-1, -1);

        openlog("rpcbind", LOG_CONS, LOG_DAEMON);

        /*
         * Create the daemon directory in /var/run
         */
        if (mkdir(daemon_dir, DAEMON_DIR_MODE) == 0 || errno == EEXIST) {
                chmod(daemon_dir, DAEMON_DIR_MODE);
                chown(daemon_dir, DAEMON_UID, DAEMON_GID);
        } else {
                syslog(LOG_ERR, "failed to create \"%s\": %m", daemon_dir);
        }

        /*
         * These privileges are required for the t_bind check rpcbind uses
         * to determine whether a service is still live or not.
         */
        can_do_mlp = priv_ineffect(PRIV_NET_BINDMLP);
        if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET, DAEMON_UID,
            DAEMON_GID, PRIV_NET_PRIVADDR, PRIV_SYS_NFS,
            can_do_mlp ? PRIV_NET_BINDMLP : NULL, NULL) == -1) {
                fprintf(stderr, "Insufficient privileges\n");
                exit(1);
        }

        myzone = getzoneid();

        /*
         * Set number of file descriptors to unlimited
         */
        if (!rpc_control(RPC_SVC_USE_POLLFD, &rpc_svc_fdunlim)) {
                syslog(LOG_INFO, "unable to set number of FD to unlimited");
        }

        /*
         * Tell RPC that we want automatic thread mode.
         * A new thread will be spawned for each request.
         */
        if (!rpc_control(RPC_SVC_MTMODE_SET, &rpc_svc_mode)) {
                syslog(LOG_ERR, "unable to set automatic MT mode");
                exit(1);
        }

        /*
         * Enable non-blocking mode and maximum record size checks for
         * connection oriented transports.
         */
        if (!rpc_control(RPC_SVC_CONNMAXREC_SET, &maxrecsz)) {
                syslog(LOG_INFO, "unable to set RPC max record size");
        }

        {
                /*
                 * rpcbind is the first application to encounter the
                 * various netconfig files.  check_netconfig() verifies
                 * that they are set up correctly and complains loudly
                 * if not.
                 */
                int trouble;

                trouble = check_netconfig();
                if (trouble) {
                        syslog(LOG_ERR, "%s: found %d errors with network "
                            "configuration files. Exiting.", argv[0], trouble);
                        fprintf(stderr, "%s: found %d errors with network "
                            "configuration files. Exiting.\n",
                            argv[0], trouble);
                        exit(1);
                }
        }

        loopback_dg = "";
        loopback_vc = "";
        loopback_vc_ord = "";
#ifdef PORTMAP
        udptrans = "";
        tcptrans = "";
#endif

        ipv6flag = Is_ipv6present();
        rpcb_check_init();

        nc_handle = setnetconfig();     /* open netconfig file */
        if (nc_handle == NULL) {
                syslog(LOG_ERR, "could not read /etc/netconfig");
                exit(1);
        }
        while ((nconf = getnetconfig(nc_handle)) != NULL) {
                if (nconf->nc_flag & NC_VISIBLE)
                        init_transport(nconf);
        }
        endnetconfig(nc_handle);

        if ((loopback_dg[0] == '\0') && (loopback_vc[0] == '\0') &&
            (loopback_vc_ord[0] == '\0')) {
                syslog(LOG_ERR, "could not find loopback transports");
                exit(1);
        }

        if (warmstart) {
                read_warmstart();
        }

        /* Create terminate signal handler for graceful exit */
        if (thr_create(NULL, 0, (void *(*)(void *))terminate, NULL, 0, NULL)) {
                syslog(LOG_ERR, "Failed to create terminate thread");
                exit(1);
        }

        if (debugging) {
                printf("rpcbind debugging enabled.");
                if (doabort) {
                        printf("  Will abort on errors!\n");
                } else {
                        printf("\n");
                }
        } else {
                detachfromtty();
        }

        /* These are basic privileges we do not need */
        __fini_daemon_priv(PRIV_PROC_EXEC, PRIV_PROC_SESSION,
            PRIV_FILE_LINK_ANY, PRIV_PROC_INFO, (char *)NULL);

        svc_run();
        syslog(LOG_ERR, "svc_run returned unexpectedly");
        rpcbind_abort();
        /* NOTREACHED */
}

/*
 * Increments a counter each time a problem is found with the network
 * configuration information.
 */
static int
check_netconfig(void)
{
        void    *nc;
        void    *dlcookie;
        int     busted = 0;
        int     i;
        int     lo_clts_found = 0, lo_cots_found = 0, lo_cotsord_found = 0;
        struct netconfig        *nconf, *np;
        struct stat     sb;

        nc = setnetconfig();
        if (nc == NULL) {
                if (debugging)
                        fprintf(stderr,
                            "setnetconfig() failed:  %s\n", nc_sperror());
                syslog(LOG_ALERT, "setnetconfig() failed:  %s", nc_sperror());
                return (1);
        }
        while ((np = getnetconfig(nc)) != NULL) {
                if ((np->nc_flag & NC_VISIBLE) == 0)
                        continue;
                if (debugging)
                        fprintf(stderr, "checking netid \"%s\"\n",
                            np->nc_netid);
                if (strcmp(np->nc_protofmly, NC_LOOPBACK) == 0)
                        switch (np->nc_semantics) {
                        case NC_TPI_CLTS:
                                lo_clts_found = 1;
                                break;

                        case NC_TPI_COTS:
                                lo_cots_found = 1;
                                break;

                        case NC_TPI_COTS_ORD:
                                lo_cotsord_found = 1;
                                break;
                        }
                if (stat(np->nc_device, &sb) == -1 && errno == ENOENT) {
                        if (debugging)
                                fprintf(stderr, "\tdevice %s does not exist\n",
                                    np->nc_device);
                        syslog(LOG_ERR, "netid %s:  device %s does not exist",
                            np->nc_netid, np->nc_device);
                        busted++;
                } else
                        if (debugging)
                                fprintf(stderr, "\tdevice %s present\n",
                                    np->nc_device);
                for (i = 0; i < np->nc_nlookups; i++) {
                        char    *libname = np->nc_lookups[i];

                        if ((dlcookie = dlopen(libname, RTLD_LAZY)) == NULL) {
                                char *dlerrstr;

                                dlerrstr = dlerror();
                                if (debugging) {
                                        fprintf(stderr, "\tnetid %s: dlopen of "
                                            "name-to-address library %s "
                                            "failed\ndlerror: %s",
                                            np->nc_netid, libname,
                                            dlerrstr ? dlerrstr : "");
                                }
                                syslog(LOG_ERR, "netid %s:  dlopen of "
                                    "name-to-address library %s failed",
                                    np->nc_netid, libname);
                                if (dlerrstr)
                                        syslog(LOG_ERR, "%s", dlerrstr);
                                busted++;
                        } else {
                                if (debugging)
                                        fprintf(stderr, "\tdlopen of "
                                            "name-to-address library %s "
                                            "succeeded\n", libname);
                                (void) dlclose(dlcookie);
                        }
                }
                nconf = getnetconfigent(np->nc_netid);

                if (!check_hostserv(nconf, HOST_SELF, ""))
                        busted++;
                if (!check_hostserv(nconf, HOST_SELF_CONNECT, ""))
                        busted++;
                if (!check_hostserv(nconf, HOST_SELF, "rpcbind"))
                        busted++;
                if (!check_hostserv(nconf, HOST_SELF_CONNECT, "rpcbind"))
                        busted++;

                freenetconfigent(nconf);
        }
        endnetconfig(nc);

        if (lo_clts_found) {
                if (debugging)
                        fprintf(stderr, "Found CLTS loopback transport\n");
        } else {
                syslog(LOG_ALERT, "no CLTS loopback transport found\n");
                if (debugging)
                        fprintf(stderr, "no CLTS loopback transport found\n");
        }
        if (lo_cots_found) {
                if (debugging)
                        fprintf(stderr, "Found COTS loopback transport\n");
        } else {
                syslog(LOG_ALERT, "no COTS loopback transport found\n");
                if (debugging)
                        fprintf(stderr, "no COTS loopback transport found\n");
        }
        if (lo_cotsord_found) {
                if (debugging)
                        fprintf(stderr, "Found COTS ORD loopback transport\n");
        } else {
                syslog(LOG_ALERT, "no COTS ORD loopback transport found\n");
                if (debugging)
                        fprintf(stderr,
                            "no COTS ORD loopback transport found\n");
        }

        return (busted);
}

/*
 * Adds the entry into the rpcbind database.
 * If PORTMAP, then for UDP and TCP, it adds the entries for version 2 also
 * Returns 0 if succeeds, else fails
 */
static int
init_transport(struct netconfig *nconf)
{
        int fd;
        struct t_bind *taddr, *baddr;
        SVCXPRT *my_xprt;
        struct nd_addrlist *nas;
        struct nd_hostserv hs;
        static int msgprt = 0;

        if ((nconf->nc_semantics != NC_TPI_CLTS) &&
            (nconf->nc_semantics != NC_TPI_COTS) &&
            (nconf->nc_semantics != NC_TPI_COTS_ORD))
                return (1);     /* not my type */

        if ((strcmp(nconf->nc_protofmly, NC_INET6) == 0) && !ipv6flag) {
                if (!msgprt)
                        syslog(LOG_DEBUG, "/etc/netconfig has IPv6 entries but "
                            "IPv6 is not configured");
                msgprt++;
                return (1);
        }

        if ((fd = t_open(nconf->nc_device, O_RDWR, NULL)) < 0) {
                syslog(LOG_ERR, "%s: cannot open connection: %s",
                    nconf->nc_netid, t_errlist[t_errno]);
                return (1);
        }

        if (is_system_labeled() &&
            (strcmp(nconf->nc_protofmly, NC_INET) == 0 ||
            strcmp(nconf->nc_protofmly, NC_INET6) == 0) &&
            setopt_anon_mlp(fd) == -1) {
                syslog(LOG_ERR, "%s: couldn't set SO_ANON_MLP option",
                    nconf->nc_netid);
        }

        /*
         * Negotiate for returning the ucred of the caller. This should
         * done before enabling the endpoint for service via
         * t_bind() so that requests to rpcbind contain the uid.
         */
        svc_fd_negotiate_ucred(fd);

        taddr = (struct t_bind *)t_alloc(fd, T_BIND, T_ADDR);
        baddr = (struct t_bind *)t_alloc(fd, T_BIND, T_ADDR);
        if ((baddr == NULL) || (taddr == NULL)) {
                syslog(LOG_ERR, "%s: cannot allocate netbuf: %s",
                    nconf->nc_netid, t_errlist[t_errno]);
                exit(1);
        }

        /* Get rpcbind's address on this transport */
        hs.h_host = HOST_SELF;
        hs.h_serv = servname;
        if (netdir_getbyname(nconf, &hs, &nas))
                goto error;

        /* Copy the address */
        taddr->addr.len = nas->n_addrs->len;
        memcpy(taddr->addr.buf, nas->n_addrs->buf, (int)nas->n_addrs->len);
        netdir_free((char *)nas, ND_ADDRLIST);

        if (nconf->nc_semantics == NC_TPI_CLTS)
                taddr->qlen = 0;
        else
                taddr->qlen = listen_backlog;

        if (strcmp(nconf->nc_proto, NC_TCP) == 0) {
                /*
                 * Sm: If we are running then set SO_REUSEADDR option
                 * so that we can bind to our preferred address even if
                 * previous connections are in FIN_WAIT state
                 */
                if (setopt_reuseaddr(fd) == -1) {
                        syslog(LOG_ERR, "Couldn't set SO_REUSEADDR option");
                }
        }

        if (t_bind(fd, taddr, baddr) != 0) {
                syslog(LOG_ERR, "%s: cannot bind: %s",
                    nconf->nc_netid, t_errlist[t_errno]);
                goto error;
        }

        if (nconf->nc_semantics != NC_TPI_CLTS && taddr->qlen != baddr->qlen)
                syslog(LOG_NOTICE, "%s: unable to set listen backlog to %d "
                    "(negotiated: %d)", nconf->nc_netid, taddr->qlen,
                    baddr->qlen);

        if (memcmp(taddr->addr.buf, baddr->addr.buf, (int)baddr->addr.len)) {
                syslog(LOG_ERR, "%s: address in use", nconf->nc_netid);
                goto error;
        }

        my_xprt = svc_tli_create(fd, nconf, baddr, 0, 0);
        if (my_xprt == NULL) {
                syslog(LOG_ERR, "%s: could not create service",
                    nconf->nc_netid);
                goto error;
        }

        /* set up multicast address for RPC CALL_IT, IPv6 */

        if ((strcmp(nconf->nc_protofmly, NC_INET6) == 0) &&
            (strcmp(nconf->nc_proto, NC_UDP) == 0)) {
                if (setup_callit(fd) < 0) {
                        syslog(LOG_ERR, "Unable to join IPv6 multicast group "
                            "for rpc broadcast %s", RPCB_MULTICAST_ADDR);
                }
        }

        if (strcmp(nconf->nc_proto, NC_TCP) == 0) {
                svc_control(my_xprt, SVCSET_KEEPALIVE, (void *) TRUE);
        }

#ifdef PORTMAP
        /*
         * Register both the versions for tcp/ip and udp/ip
         */
        if ((strcmp(nconf->nc_protofmly, NC_INET) == 0) &&
            ((strcmp(nconf->nc_proto, NC_TCP) == 0) ||
            (strcmp(nconf->nc_proto, NC_UDP) == 0))) {
                PMAPLIST *pml;

                if (!svc_register(my_xprt, PMAPPROG, PMAPVERS,
                    pmap_service, 0)) {
                        syslog(LOG_ERR, "could not register on %s",
                            nconf->nc_netid);
                        goto error;
                }
                pml = malloc(sizeof (PMAPLIST));
                if (pml == NULL) {
                        syslog(LOG_ERR, "no memory!");
                        exit(1);
                }
                pml->pml_map.pm_prog = PMAPPROG;
                pml->pml_map.pm_vers = PMAPVERS;
                pml->pml_map.pm_port = PMAPPORT;
                if (strcmp(nconf->nc_proto, NC_TCP) == 0) {
                        if (tcptrans[0]) {
                                syslog(LOG_ERR,
                                "cannot have more than one TCP transport");
                                goto error;
                        }
                        tcptrans = strdup(nconf->nc_netid);
                        pml->pml_map.pm_prot = IPPROTO_TCP;

                        /* Let's snarf the universal address */
                        /* "h1.h2.h3.h4.p1.p2" */
                        tcp_uaddr = taddr2uaddr(nconf, &baddr->addr);
                } else {
                        if (udptrans[0]) {
                                syslog(LOG_ERR,
                                "cannot have more than one UDP transport");
                                goto error;
                        }
                        udptrans = strdup(nconf->nc_netid);
                        pml->pml_map.pm_prot = IPPROTO_UDP;

                        /* Let's snarf the universal address */
                        /* "h1.h2.h3.h4.p1.p2" */
                        udp_uaddr = taddr2uaddr(nconf, &baddr->addr);
                }
                pml->pml_next = list_pml;
                list_pml = pml;

                /* Add version 3 information */
                pml = malloc(sizeof (PMAPLIST));
                if (pml == NULL) {
                        syslog(LOG_ERR, "no memory!");
                        exit(1);
                }
                pml->pml_map = list_pml->pml_map;
                pml->pml_map.pm_vers = RPCBVERS;
                pml->pml_next = list_pml;
                list_pml = pml;

                /* Add version 4 information */
                pml = malloc(sizeof (PMAPLIST));
                if (pml == NULL) {
                        syslog(LOG_ERR, "no memory!");
                        exit(1);
                }
                pml->pml_map = list_pml->pml_map;
                pml->pml_map.pm_vers = RPCBVERS4;
                pml->pml_next = list_pml;
                list_pml = pml;

                /* Also add version 2 stuff to rpcbind list */
                rbllist_add(PMAPPROG, PMAPVERS, nconf, &baddr->addr);
        }
#endif

        /* version 3 registration */
        if (!svc_reg(my_xprt, RPCBPROG, RPCBVERS, rpcb_service_3, NULL)) {
                syslog(LOG_ERR, "could not register %s version 3",
                    nconf->nc_netid);
                goto error;
        }
        rbllist_add(RPCBPROG, RPCBVERS, nconf, &baddr->addr);

        /* version 4 registration */
        if (!svc_reg(my_xprt, RPCBPROG, RPCBVERS4, rpcb_service_4, NULL)) {
                syslog(LOG_ERR, "could not register %s version 4",
                    nconf->nc_netid);
                goto error;
        }
        rbllist_add(RPCBPROG, RPCBVERS4, nconf, &baddr->addr);

        if (strcmp(nconf->nc_protofmly, NC_LOOPBACK) == 0) {
                if (nconf->nc_semantics == NC_TPI_CLTS)
                        loopback_dg = strdup(nconf->nc_netid);
                else if (nconf->nc_semantics == NC_TPI_COTS)
                        loopback_vc = strdup(nconf->nc_netid);
                else if (nconf->nc_semantics == NC_TPI_COTS_ORD)
                        loopback_vc_ord = strdup(nconf->nc_netid);
        }

        /* decide if bound checking works for this transport */
        (void) add_bndlist(nconf, taddr, baddr);

        /*
         * rmtcall only supported on CLTS transports for now.
         */
        if (nconf->nc_semantics == NC_TPI_CLTS)
                (void) create_rmtcall_fd(nconf);

        (void) t_free((char *)taddr, T_BIND);
        (void) t_free((char *)baddr, T_BIND);
        return (0);
error:
        (void) t_free((char *)taddr, T_BIND);
        (void) t_free((char *)baddr, T_BIND);
        (void) t_close(fd);
        return (1);
}

static void
rbllist_add(ulong_t prog, ulong_t vers, struct netconfig *nconf,
    struct netbuf *addr)
{
        rpcblist_ptr rbl;

        rbl = malloc(sizeof (rpcblist));
        if (rbl == NULL) {
                syslog(LOG_ERR, "no memory!");
                exit(1);
        }

        rbl->rpcb_map.r_prog = prog;
        rbl->rpcb_map.r_vers = vers;
        rbl->rpcb_map.r_netid = strdup(nconf->nc_netid);
        rbl->rpcb_map.r_addr = taddr2uaddr(nconf, addr);
        if (rbl->rpcb_map.r_addr == NULL)
                rbl->rpcb_map.r_addr = strdup("");
        rbl->rpcb_map.r_owner = strdup(superuser);

        if (rbl->rpcb_map.r_netid == NULL || rbl->rpcb_map.r_addr == NULL ||
            rbl->rpcb_map.r_owner == NULL) {
                syslog(LOG_ERR, "no memory!");
                exit(1);
        }

        rbl->rpcb_next = list_rbl;      /* Attach to global list */
        list_rbl = rbl;
}

/*
 * Catch the signal and die, if not SIGHUP
 */
static void
terminate(void)
{
        int sig;

        for (;;) {
                sig = sigwait(&sigwaitset);
                if (sig == SIGHUP) {
                        rpcb_check_init();
                        continue;
                }
                if (sig != -1 || errno != EINTR)
                        break;
        }

        syslog(LOG_ERR, "rpcbind terminating on signal %d.", sig);

        rw_wrlock(&list_rbl_lock);
#ifdef PORTMAP
        rw_wrlock(&list_pml_lock);
#endif
        write_warmstart();      /* Dump yourself */

        exit(2);
}

void
rpcbind_abort(void)
{
        /*
         * We need to hold write locks to make sure
         * write_warmstart() is executed exactly once
         */
        rw_wrlock(&list_rbl_lock);
#ifdef PORTMAP
        rw_wrlock(&list_pml_lock);
#endif
        write_warmstart();      /* Dump yourself */

        abort();
}

/*
 * detach from tty
 */
static void
detachfromtty(void)
{
        close(0);
        close(1);
        close(2);
        switch (forkall()) {
        case (pid_t)-1:
                perror("fork");
                break;
        case 0:
                break;
        default:
                exit(0);
        }
        setsid();
        (void) open("/dev/null", O_RDWR, 0);
        dup(0);
        dup(0);
}

static int
convert_int(int *val, char *str)
{
        long lval;

        if (str == NULL || !isdigit(*str))
                return (-1);

        lval = strtol(str, &str, 10);
        if (*str != '\0' || lval > INT_MAX)
                return (-2);

        *val = (int)lval;
        return (0);
}

static int get_smf_iprop(const char *, int, int, int);

/* get command line options */
static void
parseargs(int argc, char *argv[])
{
        int c;
        int tmp;

        listen_backlog = get_smf_iprop("listen_backlog", 64, 1, INT_MAX);

        while ((c = getopt(argc, argv, "dwal:")) != EOF) {
                switch (c) {
                case 'd':
                        debugging = 1;
                        break;
                case 'a':
                        doabort = 1;    /* when debugging, do an abort on */
                        break;          /* errors; for rpcbind developers */
                                        /* only! */
                case 'w':
                        warmstart = 1;
                        break;

                case 'l':
                        if (convert_int(&tmp, optarg) != 0 || tmp < 1) {
                                (void) fprintf(stderr, "%s: invalid "
                                    "listen_backlog option, using defaults\n",
                                    argv[0]);
                                break;
                        }
                        listen_backlog = tmp;
                        break;
                default:        /* error */
                        fprintf(stderr,
                            "usage: rpcbind [-d] [-w] [-l listen_backlog]\n");
                        exit(1);
                }
        }
        if (doabort && !debugging) {
                fprintf(stderr,
                    "-a (abort) specified without -d "
                    "(debugging) -- ignored.\n");
                doabort = 0;
        }
}

static int
setopt_int(int fd, int level, int name, int value)
{
        struct t_optmgmt req, resp;
        struct {
                struct opthdr opt;
                int value;
        } optdata;

        optdata.opt.level = level;
        optdata.opt.name = name;
        optdata.opt.len = sizeof (int);

        optdata.value = value;

        req.flags = T_NEGOTIATE;
        req.opt.len = sizeof (optdata);
        req.opt.buf = (char *)&optdata;

        resp.flags = 0;
        resp.opt.buf = (char *)&optdata;
        resp.opt.maxlen = sizeof (optdata);

        if (t_optmgmt(fd, &req, &resp) < 0 || resp.flags != T_SUCCESS) {
                t_error("t_optmgmt");
                return (-1);
        }
        return (0);
}

static int
setopt_reuseaddr(int fd)
{
        return (setopt_int(fd, SOL_SOCKET, SO_REUSEADDR, 1));
}

static int
setopt_anon_mlp(int fd)
{
        return (setopt_int(fd, SOL_SOCKET, SO_ANON_MLP, 1));
}

static int
setup_callit(int fd)
{
        struct ipv6_mreq mreq;
        struct t_optmgmt req, resp;
        struct opthdr *opt;
        char reqbuf[ sizeof (struct ipv6_mreq) + 24];
        struct ipv6_mreq *pmreq;

        opt = (struct opthdr *)reqbuf;

        opt->level = IPPROTO_IPV6;
        opt->name = IPV6_ADD_MEMBERSHIP;
        opt->len = sizeof (struct ipv6_mreq);

        /* multicast address */
        (void) inet_pton(AF_INET6, RPCB_MULTICAST_ADDR,
            mreq.ipv6mr_multiaddr.s6_addr);
        mreq.ipv6mr_interface = 0;

        /* insert it into opt */
        pmreq = (struct ipv6_mreq *)&reqbuf[sizeof (struct opthdr)];
        memcpy(pmreq, &mreq, sizeof (struct ipv6_mreq));

        req.flags = T_NEGOTIATE;
        req.opt.len = sizeof (struct opthdr) + opt->len;
        req.opt.buf = (char *)opt;

        resp.flags = 0;
        resp.opt.buf = reqbuf;
        resp.opt.maxlen = sizeof (reqbuf);

        if (t_optmgmt(fd, &req, &resp) < 0 || resp.flags != T_SUCCESS) {
                t_error("t_optmgmt");
                return (-1);
        }
        return (0);
}

static boolean_t
check_hostserv(struct netconfig *nconf, const char *host, const char *serv)
{
        struct nd_hostserv nh;
        struct nd_addrlist *na;
        const char *hostname = host;
        const char *servname = serv;
        int retval;

        if (strcmp(host, HOST_SELF) == 0)
                hostname = "HOST_SELF";
        else if (strcmp(host, HOST_SELF_CONNECT) == 0)
                hostname = "HOST_SELF_CONNECT";

        if (serv[0] == '\0')
                servname = "<any>";

        nh.h_host = (char *)host;
        nh.h_serv = (char *)serv;

        retval = netdir_getbyname(nconf, &nh, &na);
        if (retval != ND_OK || na->n_cnt == 0) {
                if (retval == ND_OK)
                        netdir_free(na, ND_ADDRLIST);

                syslog(LOG_ALERT, "netid %s: cannot find an address for host "
                    "%s, service \"%s\"", nconf->nc_netid, hostname, servname);
                if (debugging) {
                        (void) fprintf(stderr, "\tnetdir_getbyname for %s, "
                            "service \"%s\" failed\n", hostname, servname);
                }
                return (B_FALSE);
        }
        netdir_free(na, ND_ADDRLIST);

        if (debugging) {
                (void) fprintf(stderr, "\tnetdir_getbyname for %s, service "
                    "service \"%s\" succeeded\n", hostname, servname);
        }
        return (B_TRUE);
}

/* Maximum outstanding syslog requests */
#define MAXLOG          100
/* Maximum length: the messages generated are fairly short; no hostnames. */
#define MAXMSG          128

typedef struct logmsg {
        struct logmsg   *log_next;
        int             log_pri;
        char            log_msg[MAXMSG];
} logmsg;

static logmsg *loghead = NULL;
static logmsg **logtailp = &loghead;
static mutex_t logmutex = DEFAULTMUTEX;
static cond_t logcond = DEFAULTCV;
static int logcount = 0;

/* ARGSUSED */
static void * __NORETURN
logthread(void *arg)
{
        for (;;) {
                logmsg *msg;
                (void) mutex_lock(&logmutex);
                while ((msg = loghead) == NULL)
                        (void) cond_wait(&logcond, &logmutex);

                loghead = msg->log_next;
                logcount--;
                if (loghead == NULL) {
                        logtailp = &loghead;
                        logcount = 0;
                }
                (void) mutex_unlock(&logmutex);
                syslog(msg->log_pri, "%s", msg->log_msg);
                free(msg);
        }
        /* NOTREACHED */
}

static boolean_t
get_smf_prop(const char *var, boolean_t def_val)
{
        scf_simple_prop_t *prop;
        uint8_t *val = NULL;
        boolean_t res = def_val;

        prop = scf_simple_prop_get(NULL, NULL, "config", var);
        if (prop != NULL) {
                if ((val = scf_simple_prop_next_boolean(prop)) != NULL)
                        res = (*val == 0) ? B_FALSE : B_TRUE;
                scf_simple_prop_free(prop);
        }

        if (prop == NULL || val == NULL) {
                syslog(LOG_ALERT, "no value for config/%s (%s). "
                    "Using default \"%s\"", var, scf_strerror(scf_error()),
                    def_val ? "true" : "false");
        }

        return (res);
}

static int
get_smf_iprop(const char *var, int def_val, int min, int max)
{
        scf_simple_prop_t *prop;
        int64_t *val = NULL;
        int res = def_val;

        prop = scf_simple_prop_get(NULL, NULL, "config", var);
        if (prop != NULL) {
                if ((val = scf_simple_prop_next_integer(prop)) != NULL) {
                        if (*val < min || *val > max)
                                syslog(LOG_ALERT, "value for config/%s out of "
                                    "range. Using default %d", var, def_val);
                        else
                                res = (int)*val;
                }
                scf_simple_prop_free(prop);
        }

        if (prop == NULL || val == NULL) {
                syslog(LOG_ALERT, "no value for config/%s (%s). "
                    "Using default %d", var, scf_strerror(scf_error()),
                    def_val);
        }

        return (res);
}

/*
 * Initialize: read the configuration parameters from SMF.
 * This function must be idempotent because it can be called from the
 * signal handler.
 */
static void
rpcb_check_init(void)
{
        thread_t tid;
        int max_threads;
        static int thr_running;

        wrap_enabled = get_smf_prop("enable_tcpwrappers", B_FALSE);
        verboselog = get_smf_prop("verbose_logging", B_FALSE);
        allow_indirect = get_smf_prop("allow_indirect", B_TRUE);
        local_only = get_smf_prop("local_only", B_TRUE);

        if (wrap_enabled && !thr_running) {
                (void) thr_create(NULL, 0, logthread, NULL, THR_DETACHED, &tid);
                thr_running = 1;
        }

        /*
         * Set the maximum number of threads.
         */
        max_threads = get_smf_iprop("max_threads", 72, 1, INT_MAX);
        if (!rpc_control(RPC_SVC_THRMAX_SET, &max_threads)) {
                int tmp;

                /*
                 * The following rpc_control() call cannot fail
                 */
                if (!rpc_control(RPC_SVC_THRMAX_GET, &tmp))
                        assert(0);

                if (tmp != max_threads) {
                        syslog(LOG_ERR, "setting max_threads to %d failed, "
                            "using %d worker threads", max_threads, tmp);
                        max_threads = tmp;
                }
        }

        /*
         * Set rpcb_rmtcalls_max.
         */
        if (max_threads < reserved_threads)
                set_rpcb_rmtcalls_max(0);
        else
                set_rpcb_rmtcalls_max(max_threads - reserved_threads);
}

/*
 * qsyslog() - queue a request for syslog(); if syslog blocks, the other
 * thread blocks; we make sure we don't run out of memory by allowing
 * only a limited number of outstandig syslog() requests.
 */
void
qsyslog(int pri, const char *fmt, ...)
{
        logmsg *msg = malloc(sizeof (*msg));
        va_list ap;

        if (msg == NULL)
                return;

        msg->log_pri = pri;

        va_start(ap, fmt);
        (void) vsnprintf(msg->log_msg, sizeof (msg->log_msg), fmt, ap);
        va_end(ap);

        msg->log_next = NULL;

        (void) mutex_lock(&logmutex);
        if (logcount < MAXLOG) {
                if (logcount == 0)
                        (void) cond_signal(&logcond);
                logcount++;
                *logtailp = msg;
                logtailp = &msg->log_next;
                (void) mutex_unlock(&logmutex);
        } else {
                (void) mutex_unlock(&logmutex);
                free(msg);
        }
}