dispatch.c

   1 /* $OpenBSD: dispatch.c,v 1.22 2008/10/31 15:05:34 stevesk Exp $ */
   2 /*
   3  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include "includes.h"
  27
  28 #include <sys/types.h>
  29
  30 #include <signal.h>
  31 #include <stdarg.h>
  32
  33 #include "ssh1.h"
  34 #include "ssh2.h"
  35 #include "log.h"
  36 #include "dispatch.h"
  37 #include "packet.h"
  38 #include "compat.h"
  39
  40 #define DISPATCH_MAX    255
  41
  42 dispatch_fn *dispatch[DISPATCH_MAX];
  43
  44 void
  45 dispatch_protocol_error(int type, u_int32_t seq, void *ctxt)
  46 {
  47         logit("dispatch_protocol_error: type %d seq %u", type, seq);
  48         if (!compat20)
  49                 fatal("protocol error");
  50         packet_start(SSH2_MSG_UNIMPLEMENTED);
  51         packet_put_int(seq);
  52         packet_send();
  53         packet_write_wait();
  54 }
  55 void
  56 dispatch_protocol_ignore(int type, u_int32_t seq, void *ctxt)
  57 {
  58         logit("dispatch_protocol_ignore: type %d seq %u", type, seq);
  59 }
  60 void
  61 dispatch_init(dispatch_fn *dflt)
  62 {
  63         u_int i;
  64         for (i = 0; i < DISPATCH_MAX; i++)
  65                 dispatch[i] = dflt;
  66 }
  67 void
  68 dispatch_range(u_int from, u_int to, dispatch_fn *fn)
  69 {
  70         u_int i;
  71
  72         for (i = from; i <= to; i++) {
  73                 if (i >= DISPATCH_MAX)
  74                         break;
  75                 dispatch[i] = fn;
  76         }
  77 }
  78 void
  79 dispatch_set(int type, dispatch_fn *fn)
  80 {
  81         dispatch[type] = fn;
  82 }
  83 void
  84 dispatch_run(int mode, volatile sig_atomic_t *done, void *ctxt)
  85 {
  86         for (;;) {
  87                 int type;
  88                 u_int32_t seqnr;
  89
  90                 if (mode == DISPATCH_BLOCK) {
  91                         type = packet_read_seqnr(&seqnr);
  92                 } else {
  93                         type = packet_read_poll_seqnr(&seqnr);
  94                         if (type == SSH_MSG_NONE)
  95                                 return;
  96                 }
  97                 if (type > 0 && type < DISPATCH_MAX && dispatch[type] != NULL)
  98                         (*dispatch[type])(type, seqnr, ctxt);
  99                 else
 100                         packet_disconnect("protocol error: rcvd type %d", type);
 101                 if (done != NULL && *done)
 102                         return;
 103         }
 104 }