openssh/dispatch.c

136 lines
3.5 KiB
C

/* $OpenBSD: dispatch.c,v 1.32 2019/01/19 21:33:13 djm Exp $ */
/*
* Copyright (c) 2000 Markus Friedl. All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#include "includes.h"
#include <sys/types.h>
#include <signal.h>
#include <stdarg.h>
#include "ssh2.h"
#include "log.h"
#include "dispatch.h"
#include "packet.h"
#include "compat.h"
#include "ssherr.h"
int
dispatch_protocol_error(int type, u_int32_t seq, struct ssh *ssh)
{
int r;
logit("dispatch_protocol_error: type %d seq %u", type, seq);
if ((r = sshpkt_start(ssh, SSH2_MSG_UNIMPLEMENTED)) != 0 ||
(r = sshpkt_put_u32(ssh, seq)) != 0 ||
(r = sshpkt_send(ssh)) != 0 ||
(r = ssh_packet_write_wait(ssh)) != 0)
sshpkt_fatal(ssh, r, "%s", __func__);
return 0;
}
int
dispatch_protocol_ignore(int type, u_int32_t seq, struct ssh *ssh)
{
logit("dispatch_protocol_ignore: type %d seq %u", type, seq);
return 0;
}
void
ssh_dispatch_init(struct ssh *ssh, dispatch_fn *dflt)
{
u_int i;
for (i = 0; i < DISPATCH_MAX; i++)
ssh->dispatch[i] = dflt;
}
void
ssh_dispatch_range(struct ssh *ssh, u_int from, u_int to, dispatch_fn *fn)
{
u_int i;
for (i = from; i <= to; i++) {
if (i >= DISPATCH_MAX)
break;
ssh->dispatch[i] = fn;
}
}
void
ssh_dispatch_set(struct ssh *ssh, int type, dispatch_fn *fn)
{
ssh->dispatch[type] = fn;
}
int
ssh_dispatch_run(struct ssh *ssh, int mode, volatile sig_atomic_t *done)
{
int r;
u_char type;
u_int32_t seqnr;
for (;;) {
if (mode == DISPATCH_BLOCK) {
r = ssh_packet_read_seqnr(ssh, &type, &seqnr);
if (r != 0)
return r;
} else {
r = ssh_packet_read_poll_seqnr(ssh, &type, &seqnr);
if (r != 0)
return r;
if (type == SSH_MSG_NONE)
return 0;
}
if (type > 0 && type < DISPATCH_MAX &&
ssh->dispatch[type] != NULL) {
if (ssh->dispatch_skip_packets) {
debug2("skipped packet (type %u)", type);
ssh->dispatch_skip_packets--;
continue;
}
r = (*ssh->dispatch[type])(type, seqnr, ssh);
if (r != 0)
return r;
} else {
r = sshpkt_disconnect(ssh,
"protocol error: rcvd type %d", type);
if (r != 0)
return r;
return SSH_ERR_DISCONNECTED;
}
if (done != NULL && *done)
return 0;
}
}
void
ssh_dispatch_run_fatal(struct ssh *ssh, int mode, volatile sig_atomic_t *done)
{
int r;
if ((r = ssh_dispatch_run(ssh, mode, done)) != 0)
sshpkt_fatal(ssh, r, "%s", __func__);
}