/*      $NetBSD: activate.c,v 1.15 2009/04/11 07:36:43 lukem Exp $      */

/*
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software donated to Berkeley by
 * Jan-Simon Pendry.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the University 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 REGENTS 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 REGENTS 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.
 *
 *      from: Id: activate.c,v 1.2 1992/05/27 07:09:27 jsp Exp
 *      @(#)activate.c  8.3 (Berkeley) 4/28/95
 */

#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: activate.c,v 1.15 2009/04/11 07:36:43 lukem Exp $");
#endif /* not lint */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/syslog.h>
#include <sys/uio.h>

#include "portald.h"

static  int     get_request(int, struct portal_cred *, char *, size_t);
static  void    send_reply(int, int, int);

/*
 * Scan the providers list and call the
 * appropriate function.
 */
int
activate_argv(struct portal_cred *pcr, char *key, char **v, int *fdp)
{
        provider *pr;

        for (pr = providers; pr->pr_match; pr++)
                if (strcmp(v[0], pr->pr_match) == 0)
                        return ((*pr->pr_func)(pcr, key, v, fdp));

        return (ENOENT);
}

static int
get_request(int so, struct portal_cred *pcr, char *key, size_t klen)
{
        struct iovec iov[2];
        struct msghdr msg;
        ssize_t n;

        iov[0].iov_base = (caddr_t) pcr;
        iov[0].iov_len = sizeof(*pcr);
        iov[1].iov_base = key;
        iov[1].iov_len = klen;

        memset(&msg, 0, sizeof(msg));
        msg.msg_iov = iov;
        msg.msg_iovlen = 2;

        n = recvmsg(so, &msg, 0);
        if (n < 0)
                return (errno);

        if (n <= (ssize_t)sizeof(*pcr))
                return (EINVAL);

        n -= sizeof(*pcr);
        key[n] = '\0';

        return (0);
}

static void
send_reply(int so, int fd, int error)
{
        int n;
        struct iovec iov;
        struct msghdr msg;
        void *ctl = NULL;
        struct cmsghdr *cmsg;
        int *files;
        socklen_t cmsgsize;

        /*
         * Line up error code.  Don't worry about byte ordering
         * because we must be sending to the local machine.
         */
        iov.iov_base = (caddr_t) &error;
        iov.iov_len = sizeof(error);

        /*
         * Build a msghdr
         */
        memset(&msg, 0, sizeof(msg));
        msg.msg_iov = &iov;
        msg.msg_iovlen = 1;

        /*
         * If there is a file descriptor to send then
         * construct a suitable rights control message.
         */
        if (fd >= 0) {
                cmsgsize = CMSG_LEN(sizeof(*files));

                ctl = malloc(cmsgsize);
                if (ctl == NULL) {
                        syslog(LOG_WARNING, "malloc control message: %m");
                        return;
                }
                memset(ctl, 0, cmsgsize);

                cmsg = (struct cmsghdr *) ctl;
                cmsg->cmsg_len = CMSG_LEN(sizeof(int));
                cmsg->cmsg_level = SOL_SOCKET;
                cmsg->cmsg_type = SCM_RIGHTS;

                files = (int *)CMSG_DATA(cmsg);
                files[0] = fd;

                msg.msg_control = ctl;
                msg.msg_controllen = cmsgsize;
        }

        /*
         * Send to kernel...
         */
        if ((n = sendmsg(so, &msg, MSG_EOR)) < 0)
                syslog(LOG_WARNING, "send: %m");
#ifdef DEBUG
        fprintf(stderr, "sent %d bytes\n", n);
#endif
        sleep(1);       /*XXX*/
#ifdef notdef
        if (shutdown(so, 2) < 0)
                syslog(LOG_WARNING, "shutdown: %m");
#endif
        /*
         * Throw away the open file descriptor and control
         * message buffer.
         */
        if (fd >= 0)
                (void) close(fd);
        if (ctl != NULL)
                free(ctl);
}

void
activate(qelem *q, int so)
{
        struct portal_cred pcred;
        char key[MAXPATHLEN+1];
        int error;
        char **v;
        int fd = -1;

        /*
         * Read the key from the socket
         */
        error = get_request(so, &pcred, key, sizeof(key));
        if (error) {
                syslog(LOG_WARNING, "activate: recvmsg: %m");
                goto drop;
        }

#ifdef DEBUG
        fprintf(stderr, "lookup key %s\n", key);
#endif

        /*
         * Find a match in the configuration file
         */
        v = conf_match(q, key);

        /*
         * If a match existed, then find an appropriate portal
         * otherwise simply return ENOENT.
         */
        if (v) {
                error = activate_argv(&pcred, key, v, &fd);
                if (error)
                        fd = -1;
                else if (fd < 0)
                        error = -1;
        } else
                error = ENOENT;

        if (error >= 0)
                send_reply(so, fd, error);

drop:;
        close(so);
}