sbin/mount_portal/activate.c

   1 /*
   2  * Copyright (c) 1992, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  * All rights reserved.
   5  *
   6  * This code is derived from software donated to Berkeley by
   7  * Jan-Simon Pendry.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. All advertising materials mentioning features or use of this software
  18  *    must display the following acknowledgement:
  19  *      This product includes software developed by the University of
  20  *      California, Berkeley and its contributors.
  21  * 4. Neither the name of the University nor the names of its contributors
  22  *    may be used to endorse or promote products derived from this software
  23  *    without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  35  * SUCH DAMAGE.
  36  *
  37  *      @(#)activate.c  8.3 (Berkeley) 4/28/95
  38  *
  39  * $FreeBSD: src/sbin/mount_portal/activate.c,v 1.7 1999/08/28 00:13:35 peter Exp $
  40  * $DragonFly: src/sbin/mount_portal/activate.c,v 1.6 2007/05/18 17:05:12 dillon Exp $
  41  */
  42
  43 #include <errno.h>
  44 #include <string.h>
  45 #include <unistd.h>
  46 #include <sys/types.h>
  47 #include <sys/param.h>
  48 #include <sys/socket.h>
  49 #include <sys/syslog.h>
  50 #include <sys/uio.h>
  51
  52 #include "portald.h"
  53
  54 /*
  55  * Scan the providers list and call the
  56  * appropriate function.
  57  */
  58 static int
  59 activate_argv(struct portal_cred *pcr, char *key, char **v, int so, int *fdp)
  60 {
  61         provider *pr;
  62
  63         for (pr = providers; pr->pr_match; pr++)
  64                 if (strcmp(v[0], pr->pr_match) == 0)
  65                         return ((*pr->pr_func)(pcr, key, v, so, fdp));
  66
  67         return (ENOENT);
  68 }
  69
  70 static int
  71 get_request(int so, struct portal_cred *pcr, char *key, int klen)
  72 {
  73         struct iovec iov[2];
  74         struct msghdr msg;
  75         int n;
  76
  77         iov[0].iov_base = (caddr_t) pcr;
  78         iov[0].iov_len = sizeof(*pcr);
  79         iov[1].iov_base = key;
  80         iov[1].iov_len = klen;
  81
  82         memset(&msg, 0, sizeof(msg));
  83         msg.msg_iov = iov;
  84         msg.msg_iovlen = 2;
  85
  86         n = recvmsg(so, &msg, 0);
  87         if (n < 0)
  88                 return (errno);
  89
  90         if (n <= sizeof(*pcr))
  91                 return (EINVAL);
  92
  93         n -= sizeof(*pcr);
  94         key[n] = '\0';
  95
  96         return (0);
  97 }
  98
  99 static void
 100 send_reply(int so, int fd, int error)
 101 {
 102         int n;
 103         struct iovec iov;
 104         struct msghdr msg;
 105         struct {
 106                 struct cmsghdr cmsg;
 107                 int fd;
 108         } ctl;
 109
 110         /*
 111          * Line up error code.  Don't worry about byte ordering
 112          * because we must be sending to the local machine.
 113          */
 114         iov.iov_base = (caddr_t) &error;
 115         iov.iov_len = sizeof(error);
 116
 117         /*
 118          * Build a msghdr
 119          */
 120         memset(&msg, 0, sizeof(msg));
 121         msg.msg_iov = &iov;
 122         msg.msg_iovlen = 1;
 123
 124         /*
 125          * If there is a file descriptor to send then
 126          * construct a suitable rights control message.
 127          */
 128         if (fd >= 0) {
 129                 ctl.fd = fd;
 130                 ctl.cmsg.cmsg_len = sizeof(ctl);
 131                 ctl.cmsg.cmsg_level = SOL_SOCKET;
 132                 ctl.cmsg.cmsg_type = SCM_RIGHTS;
 133                 msg.msg_control = (caddr_t) &ctl;
 134                 msg.msg_controllen = ctl.cmsg.cmsg_len;
 135         }
 136
 137         /*
 138          * Send to kernel...
 139          */
 140         if ((n = sendmsg(so, &msg, 0)) < 0)
 141                 syslog(LOG_ERR, "send: %s", strerror(errno));
 142 #ifdef DEBUG
 143         fprintf(stderr, "sent %d bytes\n", n);
 144 #endif
 145         sleep(1);       /*XXX*/
 146 #ifdef notdef
 147         if (shutdown(so, SHUT_RDWR) < 0)
 148                 syslog(LOG_ERR, "shutdown: %s", strerror(errno));
 149 #endif
 150         /*
 151          * Throw away the open file descriptor
 152          */
 153         close(fd);
 154 }
 155
 156 void
 157 activate(qelem *q, int so)
 158 {
 159         struct portal_cred pcred;
 160         char key[MAXPATHLEN+1];
 161         int error;
 162         char **v;
 163         int fd = -1;
 164
 165         /*
 166          * Read the key from the socket
 167          */
 168         error = get_request(so, &pcred, key, sizeof(key));
 169         if (error) {
 170                 syslog(LOG_ERR, "activate: recvmsg: %s", strerror(error));
 171                 goto drop;
 172         }
 173
 174 #ifdef DEBUG
 175         fprintf(stderr, "lookup key %s\n", key);
 176 #endif
 177
 178         /*
 179          * Find a match in the configuration file
 180          */
 181         v = conf_match(q, key);
 182
 183         /*
 184          * If a match existed, then find an appropriate portal
 185          * otherwise simply return ENOENT.
 186          */
 187         if (v) {
 188                 error = activate_argv(&pcred, key, v, so, &fd);
 189                 if (error)
 190                         fd = -1;
 191                 else if (fd < 0)
 192                         error = -1;
 193         } else {
 194                 error = ENOENT;
 195         }
 196
 197         if (error >= 0)
 198                 send_reply(so, fd, error);
 199
 200 drop:;
 201         close(so);
 202 }