dispatch.c

   1 /* $OpenBSD: dispatch.c,v 1.21 2006/08/03 03:34:42 deraadt 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_MIN    0
  41 #define DISPATCH_MAX    255
  42
  43 dispatch_fn *dispatch[DISPATCH_MAX];
  44
  45 void
  46 dispatch_protocol_error(int type, u_int32_t seq, void *ctxt)
  47 {
  48         logit("dispatch_protocol_error: type %d seq %u", type, seq);
  49         if (!compat20)
  50                 fatal("protocol error");
  51         packet_start(SSH2_MSG_UNIMPLEMENTED);
  52         packet_put_int(seq);
  53         packet_send();
  54         packet_write_wait();
  55 }
  56 void
  57 dispatch_protocol_ignore(int type, u_int32_t seq, void *ctxt)
  58 {
  59         logit("dispatch_protocol_ignore: type %d seq %u", type, seq);
  60 }
  61 void
  62 dispatch_init(dispatch_fn *dflt)
  63 {
  64         u_int i;
  65         for (i = 0; i < DISPATCH_MAX; i++)
  66                 dispatch[i] = dflt;
  67 }
  68 void
  69 dispatch_range(u_int from, u_int to, dispatch_fn *fn)
  70 {
  71         u_int i;
  72
  73         for (i = from; i <= to; i++) {
  74                 if (i >= DISPATCH_MAX)
  75                         break;
  76                 dispatch[i] = fn;
  77         }
  78 }
  79 void
  80 dispatch_set(int type, dispatch_fn *fn)
  81 {
  82         dispatch[type] = fn;
  83 }
  84 void
  85 dispatch_run(int mode, volatile sig_atomic_t *done, void *ctxt)
  86 {
  87         for (;;) {
  88                 int type;
  89                 u_int32_t seqnr;
  90
  91                 if (mode == DISPATCH_BLOCK) {
  92                         type = packet_read_seqnr(&seqnr);
  93                 } else {
  94                         type = packet_read_poll_seqnr(&seqnr);
  95                         if (type == SSH_MSG_NONE)
  96                                 return;
  97                 }
  98                 if (type > 0 && type < DISPATCH_MAX && dispatch[type] != NULL)
  99                         (*dispatch[type])(type, seqnr, ctxt);
 100                 else
 101                         packet_disconnect("protocol error: rcvd type %d", type);
 102                 if (done != NULL && *done)
 103                         return;
 104         }
 105 }