/*      $NetBSD: svc_generic.c,v 1.18 2024/01/23 17:24:38 christos Exp $        */

/*
 * Copyright (c) 2010, Oracle America, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials
 *       provided with the distribution.
 *     * Neither the name of the "Oracle America, Inc." nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Copyright (c) 1986-1991 by Sun Microsystems Inc.
 */

/* #ident       "@(#)svc_generic.c      1.19    94/04/24 SMI" */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)svc_generic.c 1.21 89/02/28 Copyr 1988 Sun Micro";
#else
__RCSID("$NetBSD: svc_generic.c,v 1.18 2024/01/23 17:24:38 christos Exp $");
#endif
#endif

/*
 * svc_generic.c, Server side for RPC.
 *
 */

#include "namespace.h"
#include "reentrant.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <rpc/rpc.h>
#include <rpc/nettype.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <err.h>

#include "svc_fdset.h"
#include "rpc_internal.h"

#ifdef __weak_alias
__weak_alias(svc_create,_svc_create)
__weak_alias(svc_tp_create,_svc_tp_create)
__weak_alias(svc_tli_create,_svc_tli_create)
#endif

extern int __svc_vc_setflag(SVCXPRT *, int);

/*
 * The highest level interface for server creation.
 * It tries for all the nettokens in that particular class of token
 * and returns the number of handles it can create and/or find.
 *
 * It creates a link list of all the handles it could create.
 * If svc_create() is called multiple times, it uses the handle
 * created earlier instead of creating a new handle every time.
 */
int
svc_create(
        void (*dispatch)(struct svc_req *, SVCXPRT *),
        rpcprog_t prognum,              /* Program number */
        rpcvers_t versnum,              /* Version number */
        const char *nettype)            /* Networktype token */
{
        struct xlist {
                SVCXPRT *xprt;          /* Server handle */
                struct xlist *next;     /* Next item */
        } *l;
        static struct xlist *xprtlist;  /* A link list of all the handles */
        int num = 0;
        SVCXPRT *xprt;
        struct netconfig *nconf;
        void *handle;

/* VARIABLES PROTECTED BY xprtlist_lock: xprtlist */

        if ((handle = __rpc_setconf(nettype)) == NULL) {
                warnx("%s: unknown protocol %s", __func__, nettype);
                return (0);
        }
        while ((nconf = __rpc_getconf(handle)) != NULL) {
                mutex_lock(&xprtlist_lock);
                for (l = xprtlist; l; l = l->next) {
                        if (strcmp(l->xprt->xp_netid, nconf->nc_netid) == 0) {
                                /* Found an old one, use it */
                                (void) rpcb_unset(prognum, versnum, nconf);
                                if (svc_reg(l->xprt, prognum, versnum,
                                        dispatch, nconf) == FALSE)
                                        warnx("%s: could not register prog %u "
                                            "vers %u on %s", __func__,
                                            (unsigned)prognum,
                                            (unsigned)versnum, nconf->nc_netid);
                                else
                                        num++;
                                break;
                        }
                }
                if (l == NULL) {
                        /* It was not found. Now create a new one */
                        xprt = svc_tp_create(dispatch, prognum, versnum, nconf);
                        if (xprt) {
                                l = malloc(sizeof(*l));
                                if (l == NULL) {
                                        warn("%s: out of memory", __func__);
                                        mutex_unlock(&xprtlist_lock);
                                        return (0);
                                }
                                l->xprt = xprt;
                                l->next = xprtlist;
                                xprtlist = l;
                                num++;
                        }
                }
                mutex_unlock(&xprtlist_lock);
        }
        __rpc_endconf(handle);
        /*
         * In case of num == 0; the error messages are generated by the
         * underlying layers; and hence not needed here.
         */
        return (num);
}

/*
 * The high level interface to svc_tli_create().
 * It tries to create a server for "nconf" and registers the service
 * with the rpcbind. It calls svc_tli_create();
 */
SVCXPRT *
svc_tp_create(
        void (*dispatch)(struct svc_req *, SVCXPRT *),
        rpcprog_t prognum,              /* Program number */
        rpcvers_t versnum,              /* Version number */
        const struct netconfig *nconf) /* Netconfig structure for the network */
{
        SVCXPRT *xprt;

        if (nconf == NULL) {
                warnx("%s: invalid netconfig structure for prog %u vers %u",
                    __func__, (unsigned)prognum, (unsigned)versnum);
                return (NULL);
        }
        xprt = svc_tli_create(RPC_ANYFD, nconf, NULL, 0, 0);
        if (xprt == NULL) {
                return (NULL);
        }
        (void) rpcb_unset(prognum, versnum, __UNCONST(nconf));
        if (svc_reg(xprt, prognum, versnum, dispatch, nconf) == FALSE) {
                warnx("%s: Could not register prog %u vers %u on %s",
                    __func__, (unsigned)prognum, (unsigned)versnum,
                    nconf->nc_netid);
                SVC_DESTROY(xprt);
                return (NULL);
        }
        return (xprt);
}

/*
 * If fd is RPC_ANYFD, then it opens a fd for the given transport
 * provider (nconf cannot be NULL then). If the t_state is T_UNBND and
 * bindaddr is NON-NULL, it performs a t_bind using the bindaddr. For
 * NULL bindadr and Connection oriented transports, the value of qlen
 * is set to 8.
 *
 * If sendsz or recvsz are zero, their default values are chosen.
 */
SVCXPRT *
svc_tli_create(
        int fd,                         /* Connection end point */
        const struct netconfig *nconf,  /* Netconfig struct for nettoken */
        const struct t_bind *bindaddr,  /* Local bind address */
        u_int sendsz,                   /* Max sendsize */
        u_int recvsz)                   /* Max recvsize */
{
        SVCXPRT *xprt = NULL;           /* service handle */
        bool_t madefd = FALSE;          /* whether fd opened here  */
        struct __rpc_sockinfo si;
        struct sockaddr_storage ss;
        socklen_t slen;

        if (fd == RPC_ANYFD) {
                if (nconf == NULL) {
                        warnx("%s: invalid netconfig", __func__);
                        return (NULL);
                }
                fd = __rpc_nconf2fd(nconf);
                if (fd == -1) {
                        warnx("%s: could not open connection for %s", __func__,
                            nconf->nc_netid);
                        return (NULL);
                }
                __rpc_nconf2sockinfo(nconf, &si);
                madefd = TRUE;
        } else {
                /*
                 * It is an open descriptor. Get the transport info.
                 */
                if (!__rpc_fd2sockinfo(fd, &si)) {
                        warnx("%s: could not get transport information",
                            __func__);
                        return (NULL);
                }
        }

        /*
         * If the fd is unbound, try to bind it.
         */
        if (madefd || !__rpc_sockisbound(fd)) {
                if (bindaddr == NULL) {
                        if (bindresvport(fd, NULL) < 0) {
                                memset(&ss, 0, sizeof ss);
                                ss.ss_family = si.si_af;
                                ss.ss_len = si.si_alen;
                                if (bind(fd, (struct sockaddr *)(void *)&ss,
                                    (socklen_t)si.si_alen) < 0) {
                                        warn( "%s: could not bind to anonymous "
                                            "port", __func__);
                                        goto freedata;
                                }
                        }
                        if (si.si_socktype != SOCK_DGRAM &&
                            listen(fd, SOMAXCONN) == -1) {
                                warnx("%s: could not listen at anonymous port",
                                    __func__);
                                goto freedata;
                        }
                } else {
                        if (bind(fd,
                            (struct sockaddr *)bindaddr->addr.buf,
                            (socklen_t)si.si_alen) < 0) {
                                warnx("%s: could not bind to requested address",
                                    __func__);
                                goto freedata;
                        }
                        if (si.si_socktype != SOCK_DGRAM &&
                            listen(fd, (int)bindaddr->qlen) == -1) {
                                warnx("%s: could not listen at requested "
                                    "address", __func__);
                                goto freedata;
                        }
                }
        }
        /*
         * call transport specific function.
         */
        switch (si.si_socktype) {
        case SOCK_STREAM:
                slen = sizeof ss;
                if (getpeername(fd, (struct sockaddr *)(void *)&ss, &slen)
                    == 0) {
                        /* accepted socket */
                        xprt = svc_fd_create(fd, sendsz, recvsz);
                } else
                        xprt = svc_vc_create(fd, sendsz, recvsz);
                if (!nconf || !xprt)
                        break;
#if 0
                /* XXX fvdl */
                if (strcmp(nconf->nc_protofmly, "inet") == 0 ||
                    strcmp(nconf->nc_protofmly, "inet6") == 0)
                        (void) __svc_vc_setflag(xprt, TRUE);
#endif
                break;
        case SOCK_DGRAM:
                xprt = svc_dg_create(fd, sendsz, recvsz);
                break;
        default:
                warnx("%s: bad service type %u", __func__, si.si_socktype);
                goto freedata;
        }

        if (xprt == NULL)
                /*
                 * The error messages here are spitted out by the lower layers:
                 * svc_vc_create(), svc_fd_create() and svc_dg_create().
                 */
                goto freedata;

        /* Fill in type of service */
        xprt->xp_type = __rpc_socktype2seman(si.si_socktype);

        if (nconf) {
                xprt->xp_netid = strdup(nconf->nc_netid);
                xprt->xp_tp = strdup(nconf->nc_device);
                if (xprt->xp_netid == NULL || xprt->xp_tp == NULL) {
                        svc_destroy(xprt);
                        return NULL;
                }
        }
        return (xprt);

freedata:
        if (madefd)
                (void) close(fd);
        return (NULL);
}