/*
 * 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 (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
 */
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
 * Portions of this source code were derived from Berkeley
 * 4.3 BSD under license from the Regents of the University of
 * California.
 */

/*
 * svc_simple.c
 * Simplified front end to rpc.
 */

/*
 * This interface creates a virtual listener for all the services
 * started thru rpc_reg(). It listens on the same endpoint for
 * all the services and then executes the corresponding service
 * for the given prognum and procnum.
 */

#include "mt.h"
#include "rpc_mt.h"
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <rpc/rpc.h>
#include <sys/types.h>
#include <syslog.h>
#include <rpc/nettype.h>

static struct proglst {
        char *(*p_progname)();
        rpcprog_t p_prognum;
        rpcvers_t p_versnum;
        rpcproc_t p_procnum;
        SVCXPRT *p_transp;
        char *p_netid;
        char *p_xdrbuf;
        int p_recvsz;
        xdrproc_t p_inproc, p_outproc;
        struct proglst *p_nxt;
} *proglst;

static void universal();

static const char rpc_reg_err[] = "%s: %s";
static const char rpc_reg_msg[] = "rpc_reg: ";
static const char __reg_err1[] = "can't find appropriate transport";
static const char __reg_err3[] = "unsupported transport size";
static const char __no_mem_str[] = "out of memory";
/*
 * For simplified, easy to use kind of rpc interfaces.
 * nettype indicates the type of transport on which the service will be
 * listening. Used for conservation of the system resource. Only one
 * handle is created for all the services (actually one of each netid)
 * and same xdrbuf is used for same netid. The size of the arguments
 * is also limited by the recvsize for that transport, even if it is
 * a COTS transport. This may be wrong, but for cases like these, they
 * should not use the simplified interfaces like this.
 */

int
rpc_reg(const rpcprog_t prognum, const rpcvers_t versnum,
        const rpcproc_t procnum, char *(*progname)(), const xdrproc_t inproc,
        const xdrproc_t outproc, const char *nettype)
{
        struct netconfig *nconf;
        int done = FALSE;
        void *handle;
        extern mutex_t proglst_lock;

        if (procnum == NULLPROC) {
                (void) syslog(LOG_ERR, (const char *) "%s: %s %d",
                        rpc_reg_msg,
                        (const char *) "can't reassign procedure number %d",
                        NULLPROC);
                return (-1);
        }

        if (nettype == NULL)
                nettype = "netpath";            /* The default behavior */
        if ((handle = __rpc_setconf((char *)nettype)) == NULL) {
                (void) syslog(LOG_ERR, rpc_reg_err, rpc_reg_msg, __reg_err1);
                return (-1);
        }
/* VARIABLES PROTECTED BY proglst_lock: proglst */
        (void) mutex_lock(&proglst_lock);
        while (nconf = __rpc_getconf(handle)) {
                struct proglst *pl;
                SVCXPRT *svcxprt;
                int madenow;
                uint_t recvsz;
                char *xdrbuf;
                char *netid;

                madenow = FALSE;
                svcxprt = NULL;
                for (pl = proglst; pl; pl = pl->p_nxt)
                        if (strcmp(pl->p_netid, nconf->nc_netid) == 0) {
                                svcxprt = pl->p_transp;
                                xdrbuf = pl->p_xdrbuf;
                                recvsz = pl->p_recvsz;
                                netid = pl->p_netid;
                                break;
                        }

                if (svcxprt == NULL) {
                        struct t_info tinfo;

                        svcxprt = svc_tli_create(RPC_ANYFD, nconf, NULL, 0, 0);
                        if (svcxprt == NULL)
                                continue;
                        if (t_getinfo(svcxprt->xp_fd, &tinfo) == -1) {
                                char errorstr[100];

                                __tli_sys_strerror(errorstr, sizeof (errorstr),
                                                t_errno, errno);
                                (void) syslog(LOG_ERR, "%s : %s : %s",
                                        rpc_reg_msg, "t_getinfo failed",
                                        errorstr);
                                SVC_DESTROY(svcxprt);
                                continue;
                        }
                        if ((recvsz = __rpc_get_t_size(0, tinfo.tsdu)) == 0) {
                                (void) syslog(LOG_ERR, rpc_reg_err, rpc_reg_msg,
                                        __reg_err3);
                                SVC_DESTROY(svcxprt);
                                continue;
                        }
                        if (((xdrbuf = malloc((unsigned)recvsz)) == NULL) ||
                                ((netid = strdup(nconf->nc_netid)) == NULL)) {
                                (void) syslog(LOG_ERR, rpc_reg_err, rpc_reg_msg,
                                        __no_mem_str);
                                SVC_DESTROY(svcxprt);
                                break;
                        }
                        madenow = TRUE;
                }
                /*
                 * Check if this (program, version, netid) had already been
                 * registered.  The check may save a few RPC calls to rpcbind
                 */
                for (pl = proglst; pl; pl = pl->p_nxt)
                        if ((pl->p_prognum == prognum) &&
                                (pl->p_versnum == versnum) &&
                                (strcmp(pl->p_netid, netid) == 0))
                                break;
                if (pl == NULL) { /* Not yet */
                        (void) rpcb_unset(prognum, versnum, nconf);
                } else {
                        /* so that svc_reg does not call rpcb_set() */
                        nconf = NULL;
                }

                if (!svc_reg(svcxprt, prognum, versnum, universal, nconf)) {
                        (void) syslog(LOG_ERR,
                                "%s couldn't register prog %d vers %d for %s",
                                rpc_reg_msg, prognum, versnum, netid);
                        if (madenow) {
                                SVC_DESTROY(svcxprt);
                                free(xdrbuf);
                                free(netid);
                        }
                        continue;
                }

                pl = malloc(sizeof (struct proglst));
                if (pl == NULL) {
                        (void) syslog(LOG_ERR, rpc_reg_err, rpc_reg_msg,
                                        __no_mem_str);
                        if (madenow) {
                                SVC_DESTROY(svcxprt);
                                free(xdrbuf);
                                free(netid);
                        }
                        break;
                }
                pl->p_progname = progname;
                pl->p_prognum = prognum;
                pl->p_versnum = versnum;
                pl->p_procnum = procnum;
                pl->p_inproc = inproc;
                pl->p_outproc = outproc;
                pl->p_transp = svcxprt;
                pl->p_xdrbuf = xdrbuf;
                pl->p_recvsz = recvsz;
                pl->p_netid = netid;
                pl->p_nxt = proglst;
                proglst = pl;
                done = TRUE;
        }
        __rpc_endconf(handle);
        (void) mutex_unlock(&proglst_lock);

        if (done == FALSE) {
                (void) syslog(LOG_ERR,
                        (const char *) "%s cant find suitable transport for %s",
                        rpc_reg_msg, nettype);
                return (-1);
        }
        return (0);
}

/*
 * The universal handler for the services registered using registerrpc.
 * It handles both the connectionless and the connection oriented cases.
 */

static void
universal(struct svc_req *rqstp, SVCXPRT *transp)
{
        rpcprog_t prog;
        rpcvers_t vers;
        rpcproc_t proc;
        char *outdata;
        char *xdrbuf;
        struct proglst *pl;
        extern mutex_t proglst_lock;

        /*
         * enforce "procnum 0 is echo" convention
         */
        if (rqstp->rq_proc == NULLPROC) {
                if (svc_sendreply(transp, (xdrproc_t)xdr_void, NULL) == FALSE) {
                        (void) syslog(LOG_ERR,
                                (const char *) "svc_sendreply failed");
                }
                return;
        }
        prog = rqstp->rq_prog;
        vers = rqstp->rq_vers;
        proc = rqstp->rq_proc;
        (void) mutex_lock(&proglst_lock);
        for (pl = proglst; pl; pl = pl->p_nxt) {
                if (pl->p_prognum == prog && pl->p_procnum == proc &&
                        pl->p_versnum == vers &&
                        (strcmp(pl->p_netid, transp->xp_netid) == 0)) {
                        /* decode arguments into a CLEAN buffer */
                        xdrbuf = pl->p_xdrbuf;
                        /* Zero the arguments: reqd ! */
                        (void) memset(xdrbuf, 0, pl->p_recvsz);
                        /*
                         * Assuming that sizeof (xdrbuf) would be enough
                         * for the arguments; if not then the program
                         * may bomb. BEWARE!
                         */
                        if (!svc_getargs(transp, pl->p_inproc, xdrbuf)) {
                                svcerr_decode(transp);
                                (void) mutex_unlock(&proglst_lock);
                                return;
                        }
                        outdata = (*(pl->p_progname))(xdrbuf);
                        if (outdata == NULL &&
                                pl->p_outproc != (xdrproc_t)xdr_void) {
                                /* there was an error */
                                (void) mutex_unlock(&proglst_lock);
                                return;
                        }
                        if (!svc_sendreply(transp, pl->p_outproc, outdata)) {
                                (void) syslog(LOG_ERR, (const char *)
                        "rpc: rpc_reg trouble replying to prog %d vers %d",
                                prog, vers);
                                (void) mutex_unlock(&proglst_lock);
                                return;
                        }
                        /* free the decoded arguments */
                        (void) svc_freeargs(transp, pl->p_inproc, xdrbuf);
                        (void) mutex_unlock(&proglst_lock);
                        return;
                }
        }
        (void) mutex_unlock(&proglst_lock);
        /* This should never happen */
        (void) syslog(LOG_ERR, (const char *)
                "rpc: rpc_reg: never registered prog %d vers %d",
                prog, vers);
}